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Chinese Chemical Letters 2007年第6期18卷 718-721页

作者： Shu Zhang[a] Zhen Wen Zhao[a] Lei Xiong[a] bin xin[a] Wei Hua Hu[a] Shao Xiang Xiong[a]&Email:mscbj@*** [a]Beijing Mass Spectrometry Center Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

A novel sample preparation method of matrix-assisted laser desorption/ionization mass spectrometry for polystyrene was reported. Compared to the conventional dried-droplet method, the efficiency of ionization and sign... 详细信息

关键词： Polystyrene Matrix-assisted laser desorption/ionization time of flight mass spectrometry Three-layer method

Enhancements of dimethyl carbonate synthesis from methanol and carbon dioxide:The in situ hydrolysis of 2-cyanopyridine and crystal face effect of ceria

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Chinese Chemical Letters 2015年第9期26卷 1096-1100页

作者： Sheng-Ping Wang Jing-Jie Zhou Shu-Yang Zhao Yu-Jun Zhao xin-bin Ma Key Laboratory for Green Chemical Technology School of Chemical Engineering and TechnologyCollaborative Innovation Center of Chemical Science and EngineeringTianjin University

This paper describes the effect of the in situ hydrolysis of 2-cyanopyridine and its derivatives on the synthesis of dimethyl carbonate（DMC） from CO2 and methanol over *** the highest electronic charge number of the carbon in the cyanogroup,is the most effective agent to accelerate the desired reaction by a decrease of ***2（110） planes are active for the hydrolysis of 2-cyanopyridine,further enhancing the DMC formation by in situ removal of water *** DMC yield is improved drastically up to 378.5 mmol g cat^-1 from 12.8 mmol g cat^-1 with the in situ hydrolysis of 2-cyanopyridine over rod-CeO2（1 1 0） catalyst.

关键词： Dimethyl carbonate CeO2 Hydrolysis 2-Cyanopyridine Crystal face

The effect of selected alloying element additions on properties of Mg-based alloy as bioimplants： A literature review

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Frontiers of Materials Science 2013年第3期7卷 227-236页

作者： Li-Nan ZHANG Zeng-Tao HOU xin YE Zhao-bin XU Xue-Ling BAI Peng SHANG Center for Translational Medicine Research and Development Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 China

This review investigates the current application limitations of Mg and Mg alloys. The key issues hindering the application of biodegradable Mg alloys as implants are their fast degradation rate and biological consideration. We have discussed the effect of some selected alloying element additions on the properties of the Mg-based alloy, especially the nutrient elements in human （Zn, Mn, Ca, St）. Different grain sizes, phase constituents and distributions consequently influence the mechanical properties of the Mg alloys. Solution strengthening and precipitation strengthening are enhanced by the addition of alloying elements, generally improving the mechanical properties. Besides, the hot working process can also improve the mechanical properties. Combination of different processing steps is suggested to be adopted in the fabrication of Mg-based alloys. Corrosion properties of these *** alloys have been measured in vitro and in vivo. The degradation mechanism is also discussed in terms of corrosion types, rates, by- products and response of the surrounding tissues. Moreover, the clinical response and requirements of degradable implants are presented, especially for the nutrient elements （Ca, Mn, Zn, Sr）. This review provides information related to different Mg alloying elements and presents the promising candidates for an ideal implant.

关键词： magnesium alloy alloying element corrosion biodegradation

Synergistic extraction of zinc from ammoniacal solutions using a β-diketone mixed with trialkylphosphine oxide

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Rare Metals 2019年第3期38卷 270-276页

作者： Ru-Long Zhu xin-bin Li Chang Wei Hui Huang Min-Ting Li Cun-Xiong Li Fu-Li Tang Faculty of Metallurgy and Energy Engineering Kunming University of Science and Technology Yunnan Yuntong Zinc Co. Ltd

A simple comparative study of synergistic extraction of zinc from ammonium sulfate and ammonium chloride systems with mixtures of Mextral54-100 and tri-nalkylphosphine oxide(TRPO) dissolved in n-heptane was described. Various parameters affecting the extraction process were investigated. Experimental results show that extraction from ammonium sulfate is better than that from ammonium chloride under the same conditions owing to the additional complexation between zinc and chloride ions. Total ammonium concentration and pH have a significant effect on zinc extraction efficiency because of the formation of zinc ammine complexes. The synergistic effect is explained by the formation of adduct between zinc chelates and trialkylphosphine oxide. The thermodynamic data show that the extraction reaction is exothermic and stripping is endothermic. Infrared(IR) spectra of the zincloaded organic phases were also examined.

关键词： Synergistic extraction Zinc Ammonium sulfate Ammonium chloride Mextral54-100 Trialkylphosphine oxide

Overview of Research on Transformation of Multi-AUV Formations

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Complex System Modeling and Simulation 2021年第1期1卷 1-14页

作者： bin xin Junxi Zhang Jie Chen Qing Wang Yun Qu School of Automation and the State Key Laboratory of Intelligent Control and Decision of Complex SystemsBeijing Institute of TechnologyBeijing 100081China

Because of their wide detection range and rich functions,autonomous underwater vehicles(AUVs)are widely used for observing the marine environment,for exploring natural resources,for security and defense purposes,and in many other fields of *** with a single AUV,a multi-AUV formation can better perform various tasks and adapt to complex underwater *** changes in the mission or environment,a change in the UAV formation may also be *** the last decade,much progress has been made in the transformation of multi-AUV *** this paper,we aim to analyze the core concepts of multi-AUV formation transformation;summarize the effects of the AUV model,underwater environment,and communication between AUVs within formations on formation transformation;and elaborate on basic theories and implementation approaches for multi-AUV formation ***,this overview includes a bibliometric analysis of the related literature from multiple ***,some challenging issues and future research directions for multi-AUV formation transformation are highlighted.

关键词： autonomous underwater vehicle multi-AUV formation formation transformation formation control

Highly active Pd-Fe/α-Al_(2)O_(3) catalyst with the bayberry tannin as chelating promoter for CO oxidative coupling to diethyl oxalate

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Chinese Chemical Letters 2021年第2期32卷 796-800页

作者： Wei-Chao xing Ji-Min An Jing Lv Faisal Irshad Yu-Jun Zhao Sheng-Ping Wang xin-bin Ma Key Laboratory for Green Chemical Technology School of Chemical Engineering and TechnologyTianjin UniversityCollaborative Innovation Center of Chemical Science and EngineeringTianjin 300072China

A novel Pd-Fe/α-Al_(2)O_(3) catalyst was synthesized by incipient-wetness impregnation method with bayberry tannin as chelating promoter and commercial hollow column Raschig ring a-Al_(2)O_(3) as support for the synthesis of diethyl oxalate from CO and ethyl nitrite.A variety of characterization techniques including N2 physical adsorption,optical microscopy,scanning electron microscopy and energy dispersive system(SEM-EDS),inductively coupled plasma optical emission spectroscopy(ICP-OES),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),transmission electron microscopy(TEM),were employed to explore the relationship between the physicochemical properties and activity of *** indicated that a large number of phenolic hydroxyl groups in bayberry tannin can efficiently anchor the active component Pd,reduce the particle size and make the active Pd as a multi-ring distribution on the commercial a-Al2O3 suppo rt,which we re beneficial to improve the catalytic activity for the production of diethyl oxalate from CO and ethyl nitrite.0.3 wts Pd-Fe/α-Al_(2)O_(3) showed excelle nt catalytic activity and selectivity in a continuous flow,fixed-bed reactor with the loading amount of 10 mL catalysts,Under the mild reaction conditions,the space-time yield of diethyl oxalate was 978 g L^(-1) h^(-1) and CO conversion was 44% with the selectivity to diethyl oxalate of 95.5%.

关键词： Bayberry tannin Diethyl oxalate Phenolic hydroxyl groups Ethyl nitrite Pd-Fe/α-Al_(2)O_(3)

Correlation between TIMP-1 expression and liver fibrosis in two rat liver fibrosis models

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World Journal of Gastroenterology 2006年第19期12卷 3044-3049页

作者： Qing-He Nie Ya-Fei Zhang Yu-Mei Xie xin-Dong Luo bin Shao Jun Li Yong-xing Zhou Chinese PLA Centre of Diagnosis and Treatment for Infectious Diseases Tangdu Hospital Fourth Military Medical University Xi'an 710038 Shaanxi Province China

AIM： To evaluate serum TIMP-1 level and the correlation between TIMP-1 expression and liver fibrosis in immuneinduced and CCL4-induced liver fibrosis models in rats. METHODS： Immune-induced and CCL4-induced liver fibrosis models were established by dexamethasone （0.01 mg） and CCL4 respectively. Serum TIMP-1 level was detected with ELISA, while histopathological grade of liver biopsy was evaluated. Spearman rankcorrelation test was used to analyse the difference of the correlation between the TIMP-1 expression and hepatic fibrosis in the two fibrosis models. Furthermore,in situ hybridization was used to determine the expression difference of TIMP-1 mRNA in the two models. RESULTS： Positive correlation existed between serum TIMP-1 level of immune induced group and the histopathological stages of fibrosis liver of corresponding rats （Spearman rank-correlation test, rs = 0.812, P 0.05）, and the positive in situ hybridization signal of TIMP-1 mRNA was strong. In CCL4-induced liver fibrosis model, the correlation between the serum TIMP-1 level and the severity of hepatic fibrosis was not statistically significant（Spearman rank-correlation test, rs = 0.229, P 〉 0.05）. And compared with immune-induced model, the positivein situ hybridization signal of TIMP-1 mRNA was weaker, while the expression variation was higher in hepatic fibrosis of the same severity. CONCLUSION： The correlations between TIMP-1 expression and liver fibrosis in two rat liver fibrosis models are different. In immune-induced model, serum TIMP-1 level could reflect the severity of liver fibrosis, while in CCL4-induced model, the correlation between the serum TIMP-1 level and the severity of hepatic fibrosis was not statistically significant.

关键词： TIMP-1 Liver fibrosis Models, rat Immuneinduced, CCL4-induced Serum Tissue of liver

The Direct Sum Decomposition of Type G_2 Lie Algebra

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Communications in Mathematical Research 2019年第1期35卷 10-20页

作者： Zhu Xiao-yuan Hao Hong-hua xin bin Du Xian-kun School of Economics and Statistics Guangzhou UniversityGuangzhou510006 Decomposition of Economics Guangdong Peizheng CollegeGuangzhou510830 School of Mathematics Science Guizhou Normal UniversityGuiyang550001 不详

This article mainly discusses the direct sum decomposition of type G_2 Lie algebra, which, under such decomposition, is decomposed into a type A_1 simple Lie algebra and one of its modules. Four theorems are given to describe this module,which could be the direct sum of two or three irreducible modules, or the direct sum of weight modules and trivial modules, or the highest weight module.

关键词： simple Lie algebra G2 simple Lie algebra A1 direct sum decomposition the highest weight module

A review of cooperative path planning of an unmanned aerial vehicle group

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Frontiers of Information Technology & Electronic Engineering 2020年第12期21卷 1671-1694页

作者： Hao ZHANG bin xin Li-hua DOU Jie CHEN Kaoru HIROTA School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081China Department of Computational Intelligence and Systems Science Tokyo Institute of TechnologyTokyo 1528550Japan

As a cutting-edge branch of unmanned aerial vehicle(UAV)technology,the cooperation of a group of UAVs has attracted increasing attention from both civil and military sectors,due to its remarkable merits in functionality and flexibility for accomplishing complex extensive tasks,e.g.,search and rescue,fire-fighting,reconnaissance,and *** path planning(CPP)is a key problem for a UAV group in executing tasks *** this paper,an attempt is made to perform a comprehensive review of the research on CPP for UAV ***,a generalized optimization framework of CPP problems is proposed from the viewpoint of three key elements,i.e.,task,UAV group,and environment,as a basis for a comprehensive classification of different types of CPP *** following the proposed framework,a taxonomy for the classification of existing CPP problems is proposed to describe different kinds of CPPs in a unified ***,a review and a statistical analysis are presented based on the taxonomy,emphasizing the coordinative elements in the existing CPP *** addition,a collection of challenging CPP problems are provided to highlight future research directions.

关键词： Unmanned aerial vehicle group Cooperation Path planning Optimization problem

Distributed Behavior Control Method for Indoor Multi-robot Collaborative Odor Source Localization

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Distributed Behavior Control Method for Indoor Multi-robot C...