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Structure and Luminescence Characteristics of Europium Activated Strontium Silicates Sr(Eu,Bi)SiO_3 and Sr(Eu,Bi)_2SiO_4

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Chemical Research in Chinese Universities 2003年第4期19卷 450-453页

作者： YANGJing-hai GONGJie FANHou-gang ZHANGYong-jun YANGLi-li CHENGang TheInstituteofCondensedStatePhysics JilinNormalUniversitySiping136000P.R.China CollegeofMaterialsScienceandEngineering JilinUniversityChangchun130023P.R.China

Sr2SiO4∶Eu 3+ ,Bi 3+ and SrSiO 3∶Eu 3+ ,Bi 3+ samples were synthesized at high temperature and high pressure. The effect of high pressure on the structure and luminescence properties of the samples were studied. As a comparison, the samples were also prepared by the method of sol-gel at high temperature and atmospheric pressure. The SrSiO 3∶Eu 3+ ,Bi 3+ prepared at atmosphere has a hexagonal phase structure; in the pressure range of 2 34-4 10 GPa, it is transformed into a pseudo-orthorhombic structure(monoclinic), and in the pressure range of 4 10-4 15 GPa, the structure change of Sr 2SiO 4∶Eu 3+ , Bi 3+ has not been observed, it maintains the monoclinic structure of the samples synthesized at an atmospheric pressure. High pressure makes the luminescence properties of the samples changed obviously. The intensity and the relative quantum luminescent efficiency decrease, the half-width increases obviously and the red shift occurs. The changes of the luminescence properties result from the pressure-induced changes of the crystal structures.

关键词： High pressure and high temperature Activator Luminescence characteristics

A self-catalytic role of methanol in PNP-Ru pincer complex catalysed dehydrogenation

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Science China Chemistry 2016年第6期59卷 724-729页

作者： Yuan-Ye Jiang Zheng-Yang Xu hai-Zhu Yu Yao Fu Department of Chemistry and Center for Atomic Engineering of Advanced Materials Anhui University Hefei 230601 China Collaborative Innovation Center of Chemistry for Energy Materials CAS Key Laboratory of Urban Pollutant Conversion Department of Chemistry University of Science and Technology of China Hefei 230026 China

Extracting hydrogen from methanol is a safe and cost-efficient strategy for fuel supply. This process was realized recently at a mild condition with excellent efficiency by ruthenium pincer catalysts. Despite the experimental success, the associated mechanism remains under debate. With the aid of density functional theory(DFT) calculations, an updated and self-consistent mechanism which involves Me OH-catalysed dehydrogenation of ruthenium hydride intermediate and pre-protonation of the pincer ligand was present herein. This mechanism is kinetically favoured over the previously-proposed water- or formic- acid-participated ones and more consistent with the optimal experimental condition where strong base and neat methanol solvent are used.

关键词： dehydrogenation ruthenium pincer ligand methanol density functional theory

Modified Static Floor Field and Exit Choice for Pedestrian Evacuation

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Chinese Physics Letters 2012年第8期29卷 48-51页

作者： XU Yan HUANG hai-Jun YONG Gui School of Economics and Management Beijing University of Aeronautics and AstronauticsBeijing 100191 School of Statistics and Mathematics Inner Mongolia University of Finance and EconomicsHuhhot 010051

An improved floor field model is proposed to simulate the pedestrian evacuation behavior in a room with multiple exits by modifying the static floor *** modified static floor field is determined additionally by two cognitive coefficients of exit width and congestion degree around the *** logit-based discrete choice principle is used to govern the initial exit selection strategy based on the modified static floor field in such a scenario that pedestrians are distributed in the room's specified *** results show that the proposed model can better perform the evacuation *** analyses of the model parameters are also presented.

关键词： floor process specified

Transcriptome approach to understand the potential mechanisms of resistant and susceptible alfalfa(Medicago sativa L.) cultivars in response to aphid feeding

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Journal of Integrative Agriculture 2018年第11期17卷 2518-2527页

作者： TU Xiong-bing ZHAO hai-long ZHANG Ze-hua State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences College of Plant Protection Shenyang Agricultural University

Plant breeding for resistance to agricultural pests is an essential element in the development of integrated crop management systems, however, the molecular and genetic mechanisms underlying resistance are poorly understood. In this pilot study, we conducted a transcriptomic analysis of a resistant （R） and susceptible （S） variety of alfalfa, with （＋A） or without （-A） aphids （totally four treatments）. We used the resistant cultivar Zhongmu t and the susceptible cultivar Soca. A total of 3 549 mRNAs were differentially expressed, of which 1 738 up-regulated and 1 307 down-regulated genes were identified in S＋A/S-A plants, while 543 up-regulated and 331 down-regulated genes were identified in the R＋A/R-A plants. KEGG analysis mapped 112 and 546 differentially expressed genes to 8 and 17 substantially enriched pathways for Zhongmu 1 and Soca, respectively. Six shared pathways were linked to plant resistance traits, including phenylpropanoid biosynthesis associated with salicylic acid synthesis, and linoleic acid metabolism associated with both jasmonic acid and flavonoid biosynthesis. Ultimately, we proposed a preliminary regulatory mechanism of alfalfa cultivar resistance response to aphids feeding based on transcriptome analyses and published documents.

关键词： alfalfa cultivar resistance aphids transcriptomic molecular mechanism

Particle swarm optimization based space debris surveillance network scheduling

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Research in Astronomy and Astrophysics 2017年第3期17卷 87-96页

作者： hai Jiang Jing Liu Hao-Wen Cheng Yao Zhang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China University of Chinese Academy of Sciences Beijing 100049 China Space Debris Observation and Data Application Center China National Space Administration Beijing 100012 China

The increasing number of space debris has created an orbital debris environment that poses increasing impact risks to existing space systems and human space flights. For the safety of in-orbit spacecrafts, we should optimally schedule surveillance tasks for the existing facilities to allocate re- sources in a manner that most significantly improves the ability to predict and detect events involving affected spacecrafts. This paper analyzes two criteria that mainly affect the performance of a scheduling scheme and introduces an artificial intelligence algorithm into the scheduling of tasks of the space debris surveillance network. A new scheduling algorithm based on the particle swarm optimization algorithm is proposed, which can be implemented in two different ways： individual optimization and joint optimiza- tion. Numerical experiments with multiple facilities and objects are conducted based on the proposed algorithm, and simulation results have demonstrated the effectiveness of the proposed algorithm.

关键词： methods data analysis - observational catalogs - telescopes - techniques radar as-tronomy

High-Sensitive Glucose Biosensor Based on Ionic Liquid Doped Polyaniline/Prussian Blue Composite Film

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： Yao Yao Shou-guo Wu hai-hong Xu Li-wen Wang Department of Chemistry University of Science and Technology of China Hefei 230026 China Clinical Laboratory Hefei Third People's Hospital Hefei 230022 China

The Prussian blue/ionic liquid-polyaniline/multiwall carbon nanotubes (PB/IL-PANI/ MWNTs) composite film was fabricated by using cyclic voltammetry. The ion liquid acting as a lubricating agent, could enhance the electron delocalization degree and reduce the struc- tural defects of the polyaniline. The surface morphology of the composite film revealed that the PB nanoparticles have smaller size than that in pure PB film. Due to the introduction of ion liquid, the PB/IL-PANI/MWNTs composite film showed wonderful synergistic effect which can remarkably enhance sensitivity, expand linear range and broaden acidic adapt- ability for hydrogen peroxide detection. The composite film demonstrated good stability in neutral solution contrast to pure PB film, with a linear range from 2.5 μmol/L to 0.5 mmol/L and a high sensitivity of 736.8 μA·(mmol/L)?1·cm?2for H2O2detection. Based on the com- posite film, an amperometric glucose biosensor was then fabricated by immobilizing glucose oxidase. Under the optimal conditions, the biosensor also exhibits excellent response to glucose with the linear range from 12.5 μmol/L to 1.75 mmol/L and a high sensitivity of 94.79 μA·(mmol/L)?1·cm?2for H2O2. The detection limit was estimated 1.1 μmol/L. The resulting biosensor was applied to detect the blood sugar in human serum samples without any pretreatment, and the results were comparatively in agreement with the clinical assay.

关键词： Hydrogen peroxide Prussian blue Ionic liquid Glucose biosensor

Influence of sintering temperature on the structure and piezoelectric properties of ZnO-modified (Li, Na, K)NbO_(3) lead-free ceramics

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International Journal of Minerals,Metallurgy and Materials 2012年第9期19卷 843-848页

作者： hai-tao Li Bo-ping Zhang Wei-gang Yang Nan Ma School of Materials Science and Engineering He'nan University of Science and Technology Luoyang 471003 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

ZnO-modified (Li, Na, K)NbO3 lead-free ceramics with a nominal composition of Li0.06(Na0.535K0.48)0.94NbO3+0.7mol% ZnO (LNKN-ZT) was synthesized normally at 930-1000℃. The Zn ions incorporated into the A-site at a higher sintering temperaVare, which changed LNKN-Z7 to soft piezoelectric ceramics with the mechanical quality factor decreasing from 228 to 192. A phase transition from tetragonal to orthorhombic symmetry was identified by XRD analysis, and the corresponding calculation of lattice parameters was conducted at 970-980℃. Because of such transitional behavior and fine microstructure, the optimized values of piezoelectric coefficient, planar electromechanical coupling coefficient, and relative dielectric constant were obtained.

关键词： piezocemmics niobates zinc oxide modification phase transitions piezoelectricity sintering

Supercritical gasification for the treatment of o-cresol wastewater

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Journal of Environmental Sciences 2006年第4期18卷 644-649页

作者： WEI Chao-hai HU Cheng-sheng WU Chao-fei YAN Bo College of Environmental Science and Technology South China University of Technology Guangzhou 510640 China

The supercritical water gasification of phenolic wastewater without oxidant was performed to degrade pollutants and produce hydrogen-enriched gases. The simulated o-cresol wastewater was gasified at 440-650℃ and 27.6 MPa in a continuous Inconel 625 reactor with the residence time of 0.42-1.25 min. The influence of the reaction temperature, residence time, pressure, catalyst, oxidant and the pollutant concentration on the gasification efficiency was investigated. Higher temperature and longer residence time enhanced the o-cresol gasification. The TOC removal rate and hydrogen gasification rate were 90.6% and 194.6%, respectively, at the temperature of 650℃ and the residence time of 0.83 min. The product gas was mainly composed of H2, CO2, CFL and CO, among which the total molar percentage of H2 and CFL was higher than 50%. The gasification efficiency decreased with the pollutant concentration increasing. Both the catalyst and oxidant could accelerate the hydrocarbon gasification at a lower reaction temperature, in which the catalyst promoted H2 production and the oxidant enhanced CO2 generation. The intermediates of liquid effluents were analyzed and phenol was found to be the main composition. The results indicate that the supercritical gasification is a promising way for the treatment of hazardous organic wastewater.

关键词： supercritical water gasification o-cresol hydrogen-enriched gas wastewater treatment

The effect of secondary structures on the generation of characteristic events during the translocation of DNA hybrid through ?-hemolysin

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Science China Chemistry 2016年第1期59卷 135-141页

作者： Xingyong Wang Yuru Li Ting Li Lei Liu hai-Chen Wu School of Chemical Engineering University of Mining & TechnologyXuzhou Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety Institute of High Energy Physics Chinese Academy of Sciences

Nanopore has been developed to be a powerful,single-molecule analytical tool for sensing ions,small organic molecules and biomacromolecules such as proteins and ***,the identity of the analyte can be revealed by current amplitude changes and mean dwell time of the analyte binding *** some cases,generation of highly characteristic current events affords an alternative way of analyte determination with high confidence ***,we found that secondary structures in DNA/RNA hybrids might severely hinder the generation of signature events during their translocation through?-hemolysin *** this report,we propose a strategy to add a certain concentration of urea in the buffer solution for single channel recordings and validate that low concentration of urea can effectively denature the secondary structures in DNA hybrids and recover the generation of signature *** finding might be useful in other secondary structure-related nanopore sensing activities.

关键词： nanopore sensing DNA hybrid translocation signature event urea