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Environmental influence of Wuhan urban agglomeration development and strategies of environmental protection

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Journal of Environmental Sciences 2006年第3期18卷 616-623页

作者： gao Qun LIU ying-tao MAO Han-ying Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Chinese Academy of Agricultural Sciences Beijing 100081 China

In Wuhan urban agglomeration （WUA）, the population growth and concentration, the industrial development and urban sprawl have been affecting the environment ftmdamentally. Comparing with yangtze delta metropolitan region, the level of urbanization and industrialization of WUA has lagged behind for about 10 years; but the problems in environmental protection and rehabilitation are commonly serious. In the future, WUA should avoid unnecessary mistakes and seek a win-win strategy for economy and environment in its large-scale development stage. Based on the analysis of the changing of main environmental pollutants and the coupled curves in past decades, the paper discussed the important links among the urban environmental pollutions, industry growth and urban sprawl in WUA. It is concluded that the integration of economic and environmental policies in urban development is more required and significant at the large urban agglomeration region. Four proactive and long-term strategies need to be adopted to provide prior guidance and better protection for the development of WUA.

关键词： environmental problem urban development Wuhan urban agglomeration strategies

Further analyses of variation of ribosome DNA copy number and polymorphism in ciliates provide insights relevant to studies of both molecular ecology and phylogeny

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Science China(Life Sciences) 2019年第2期62卷 203-214页

作者： Yurui Wang Chundi Wang Yaohan Jiang Laura A.Katz Feng gao ying yan Institute of Evolution & Marine Biodiversity Ocean University of China Key Laboratory of Mariculture Ocean University of China Ministry of Education Department of Biological Sciences Smith College

Sequence-based approaches, such as analyses of ribosome DNA(rDNA) clone libraries and high-throughput amplicon sequencing, have been used extensively to infer evolutionary relationships and elucidate the biodiversity in microbial ***, recent studies demonstrate both r DNA copy number variation and intra-individual(intra-genomic) sequence variation in many organisms, which challenges the application of the rDNA-based surveys. In ciliates, an ecologically important clade of microbial eukaryotes, rDNA copy number and sequence variation are rarely studied. In the present study, we estimate the intraindividual small subunit rDNA(SSU r DNA) copy number and sequence variation in a wide range of taxa covering nine classes and 18 orders of the phylum Ciliophora. Our studies reveal that:(i) intra-individual sequence variation of SSU rDNA is ubiquitous in all groups of ciliates detected and the polymorphic level varies among taxa;(ii) there is a most common version of SSU rDNA sequence in each cell that is highly predominant and may represent the germline micronuclear template;(iii)compared with the most common version, other variant sequences differ in only 1–3 nucleotides, likely generated during macronuclear(somatic) amplification;(iv) the intra-cell sequence variation is unlikely to impact phylogenetic analyses;(v) the rDNA copy number in ciliates is highly variable, ranging from 103 to 106, with the highest record in Stentor roeselii. Overall,these analyses indicate the need for careful consideration of SSU r DNAvariation in analyses of the role of ciliates in ecosystems.

关键词： ciliates SSU rDNA sequence variation phylogenetic analyses rDNA copy number ecological significance

Effect of TiO_(2) addition on microstructures and properties of Mgo-Cao refractory aggregates

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Journal of Iron and Steel Research International 2024年第6期31卷 1547-1554页

作者： Shuai Zhang Jing-ran Wang Yuan-gao Li Feng-you Li Wen yan Hui-ying Shi The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Joint International Research Laboratory of Refractories and Metallurgy Wuhan 430081HubeiChina Shanxi Luweibao Taigang Refractory Co. Ltd.Taiyuan 030003ShanxiChina

MgO-CaO(40 wt.%CaO)refractory aggregates were prepared using the calcined dolomite and light-burned magnesia fine powder as raw materials and TiO_(2) as *** effect of TiO_(2) on their phase composition,microstructures and properties was investigated by X-ray diffraction and scanning electron *** properties such as bulk density,apparent porosity,relative aggregate tube strength and hydration resistance were also *** results showed that the CaTiO_(3) generated by the reaction between CaO and TiO_(2) was distributed around the CaO grain boundaries and intermittently distributed with MgO,which formed an isolation layer around CaO and greatly improved the hydration ***,the introduction of TiO_(2) promoted sintering and increased the grain size,further improving the strengths and hydration resistance of the *** addition,the most significant enhancement in the hydration resistance and strengths of the samples was achieved when 1.0-2.0 wt.%TiO_(2) was *** this case,the relative strength of aggregate increased from 33.3% to 37.3%-43.1%,and the mass gain after the hydration test decreased from 3.13% to 1.26%-1.45%.

关键词： MgO-CaO refractory aggregate TiO_(2)addition Phase composition Microstructure Hydration resistance

Intestinal Behçet's disease: A review of clinical diagnosis and treatment

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1493-1500页

作者： ying Liu Feng gao Ding-Quan yang yan Jiao Department of General Surgery The Affiliated Hospital to Changchun University of Chinese MedicineChangchun 130021Jilin ProvinceChina Department of Gastrointestinal and Colorectal Surgery China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina Department of Hepatobiliary and Pancreatic Surgery General Surgery CenterThe First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina

Behçet's disease(BD)is a chronic inflammatory disorder prone to frequent re-currences,with a high predilection for intestinal ***,the ef-ficacy and long-term effects of surgical treatment for intestinal BD are *** the current issue of World J Gastrointest Surg,Park et al conducted a retrospec-tive analysis of 31 patients with intestinal BD who received surgical *** found that elevated C-reactive protein levels and emergency surgery were poor prognostic factors for postoperative recurrence,emphasizing the adverse impact of severe inflammation on the prognosis of patients with intestinal *** work has clinical significance for evaluating the postoperative condition of intestinal *** editorial attempts to summarize the clinical diagnosis and treatment of intestinal BD,focusing on the impact of adverse factors on surgical *** hope this review will facilitate more precise postoperative management of patients with intestinal BD by clinicians.

关键词： Intestinal Behçet's disease Diagnosis Treatment Surgery Recurrence

Newton type methods for solving nonsmooth equations

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Journal of Systems Engineering and Electronics 2005年第4期16卷 811-815页

作者： gao yan School of Management Univ. of Shanghai for Science and Technology Shanghai 200093 P. R. China

Numerical methods for the solution of nonsmooth equations are studied. A new subdifferential for a locally Lipschitzian function is proposed. Based on this subdifferential, Newton methods for solving nonsmooth equations are developed and their convergence is shown. Since this subdifferential is easy to be computed, the present Newton methods can be executed easily in some applications.

关键词： nonsmooth equations newton methods subdifferential nonsmooth optimization.

Fast formation of single-unit-cell-thick and defect-rich layered double hydroxide nanosheets with highly enhanced oxygen evolution reaction for water splitting

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Nano Research 2018年第4期11卷 1883-1894页

作者： Rui gao Dongpeng yan State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Beijing Key Laboratory of Energy Conversion and Storage Materials College of Chemistry Beijing Normal University Beijing 100875 China

The development of high-efficiency electrocatalysts for oxygen evolution reactions （OERs） plays an important role in the water-splitting process. Herein, we report a facile way to obtain two-dimensional （2D） single-unit-cell-thick layered double hydroxide （LDH） nanosheets （NSs, - 1.3 nm） within only 5 min. These nanosheets presented significantly enhanced OER performance compared to bulk LDH systems fabricated using the conventional co-precipitation method. The current strategy further allowed control over the chemical compositions and electrochemical activities of the LDH NSs. For example, CoFe-LDH NSs presented the lowest overpotential of 0.28 V at 10 mA/cm2, and the NiFe-LDHs NSs showed Tafel slopes of 33.4 mV/decade and nearly 100% faradaic efficiency, thus outperforming state-of-the-art IrO2 water electrolysis catalysts. Moreover, positron annihilation lifetime spectroscopy and high-resolution transmission electron microscopy observations confirmed that rich defects and distorted lattices occurred within the 2D LDH NSs, which could supply abundant electrochemically active OER sites. Periodic calculations based on density functional theory （DFT） further showed that the CoFe- and NiFe-LDHs presented very low energy gaps and obvious spin-polarization behavior, which facilitated high electron mobility during the OER process. Therefore, this work presents a combined experimental and theoretical study on 2D single-unit-cell-thick LDH NSs with high OER activities, which have potential application in water splitting for renewable energy.

关键词： single-unit-cell defect-rich oxygen evolution reaction water splitting

An integrated current measurement system for nanopore analysis

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Chinese Science Bulletin 2014年第35期59卷 4968-4973页

作者： Rui gao Yi-Lun ying Bing-Yong yan Yi-Tao Long Key Laboratory for Advanced Materials Department of ChemistryEast China University of Science and Technology School of Information Science and Engineering East China University of Science and Technology

Nanopore-based techniques have attracted increasing attention as a unique tool for single-molecule *** accurately detect individual motions of each single molecule,nanopore techniques are used to develop an ultrasensitive current measurement *** work proposes an integrated current measurement system containing an amplifier system and a current signal acquisition system with a high current resolution and a high temporal resolution for nanopore *** exploration and achievements in instrument and signal processing endow nanopore techniques with reliability,affordability,and portability,which make a great leap toward its real applications.

关键词：测量系统纳米孔高电流集成高时间分辨率信号采集系统分子分析信号处理

Effect of lanthanum addition on microstructure and hardness of brass alloys produced by rheological squeeze casting

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Journal of Rare Earths 2022年第12期40卷 1953-1962,I0006页

作者： Wenjing gao Shuming Xing ying Wang School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China School of Mechatronics and Vehicle Engineering Zhengzhou University of TechnologyZhengzhou 450044China

The effect of La addition(0-0.30 wt%)on the microstructure and hardness of rheological squeeze casting brass alloys was experimentally *** rheological squeeze casting process is improved by controlling the wall surface crystals and melt flow rate to realise the preparation of semi-solid melt with flow,and a brass alloy workpiece with La is *** microstructure and properties of the brass alloy samples were investigated using metallography,scanning electron microscopy,energy-dispersive X-ray spectroscopy,X-ray diffraction and hardness *** results indicate that the hardness of the rheological squeeze casting brass alloy is increased by 20.4%from 108 to 130 HBW with an increase in the La content from 0 to 0.30 wt%.The micro structural analysis results show that La significantly refines the primary a-phase grains,and the main mechanism is the constitutional undercooling and heterogeneous nucleation caused by the La enrichment in the front of the solid-liquid *** squeeze pressure promotes undercooling,which improves the nucleation rate and affects the solute diffusion and nucleus *** dual effects of these two aspects aggravate the grain refinement process,consequently increasing the number of grain boundaries and improving the hardness of the brass alloy.

关键词： Rheological squeeze casting La Brass alloy Grain refinement Rare earths

The Dynamics of Two-State Public Opinion Propagation On Signed Networks

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Journal of Systems Science & Complexity 2021年第1期34卷 251-264页

作者： gao Yue FAN ying DI Zengru School of Systems Science Beijing Normal UniversityBeijing 100875China

The formation of public opinion on the network is a hot issue in the field of complex network research, and some classical dynamic models are used to solve this problem. The signed network is a particular form of the complex network, which can adequately describe the amicable and hostile relationships in complex real-world systems. However, the methods for studying the dynamic process of public opinion propagation on signed networks still require to be further discussed. In this paper, the authors pay attention to the influence of negative edges in order to design a two-state public opinion propagation mechanism suitable for signed networks. The authors first set the interaction rules between nodes and the transition rules of node states and then apply the model to synthetic and real-world signed networks. The simulation results show that there is a critical value of the negative edge *** the negative edge ratio exceeds this critical value, the evolutionary result of public opinion will change from a consistent state to a split state. This conclusion is also consistent with the distribution result of opinions within communities in the signed network. Besides, the research on the network structural balance shows that the model makes the network evolve in a more balanced direction.

关键词： Distribution of viewpoints negative edges public opinion signed network structural balance