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Bimetallic Ni-Fe catalysts derived from layered double hydroxides for CO methanation from syngas

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Frontiers of Chemical Science and Engineering 2017年第4期11卷 613-623页

作者： Tang, Honggui Li, Shuangshuang Gong, Dandan guan, yi Liu, Yuan Tianjin Univ Sch Chem Engn Dept Catalysis Sci & Technol Tianjin 300072 Peoples R China Tianjin Univ Sch Chem Engn Collaborat Innovat Ctr Chem Sci & Engn Tianjin Tianjin 300072 Peoples R China

Carbon deposition and sintering of active components such as nano particles are great challenges for Ni-based catalysts for CO methanation to generate synthetic natural gas from syngas. Facing the challenges, bimetallic catalysts with different Fe content derived from layered double hydroxide containing Ni, Fe, Mg, A1 elements were prepared by co-precipitation method. Nanoparticles of Ni-Fe alloy were supported on mixed oxides of aluminium and magnesium after calcination and reduction. The catalysts were characterized by Brunner- Emmett-Teller （BET）, X-ray diffraction, hydrogen tem- perature programmed reduction, inductively coupled plasma, X-ray photoelectron spectroscopy, transmission electron microscopy and thermogravimetric techniques, and their catalytic activity for CO methanation was investigated. The results show that the Ni-Fe alloy catalysts exhibit better catalytic performance than mono- metallic catalysts except for the Ni4Fe-red catalyst. The Ni2Fe-red catalyst shows the highest CO conversion （100% at 260-350 ~C）, as well as the highest CH4 selectivity （over 95% at 280-350 ~C）, owing to the formation of Ni-Fe alloy. In stability test, the Ni2Fe-red catalyst exhibits great improvement in both anti-sintering and resistance to carbon formation compared with the Ni0Fe-red catalyst. The strong interaction between Ni and Fe element in alloy and surface distribution of Fe element not only inhibits the sintering ofnanoparticles but restrains the formation of Ni clusters.

关键词： methanation layered double hydroxide bime-tal Ni-Fe alloy sintering carbon deposition

Advances in interscale and interdisciplinary approaches to the South China Sea

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Acta Oceanologica Sinica 2021年第11期40卷 196-199页

作者： Lingling Xie yi guan Jianyu Hu Quanan Zheng Laboratory of Coastal Ocean Variation and Disaster Prediction College of Ocean and MeteorologyGuangdong Ocean UniversityZhanjiang 524088China Key Laboratory of Climate Resources and Environments in Continent Shelf Sea and Deep OceanZhanjiang 524088China Key Laboratory of Space Ocean Remote Sensing and Applications Ministry of Natural ResourcesBeijing 100081China State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China Department of Atmospheric and Oceanic Science University of MarylandCollege Park 20742USA

The South China Sea(SCS)connects the Pacific Ocean and the Indian Ocean,and acts as an important part in regional and global climate systems(e.g.,Qu et al.,2009;Wang et al.,2009).Multi-scale dynamic and biogeochemical processes in the SCS,comprising a hot spot in marginal sea studies,have attracted great attentions from researchers(e.g.,Chen et al.,2020;Hu et al.,2020).The South China Sea Annual Meeting(SCSAM)2021,recently held on October 22–24 in Zhanjiang,China,focused on academic exchanges of the newly research results and progresses in the interdisciplinary multi-scale processes in the *** SCSAM 2021 is the eighth international workshop of the series,which started in April 2013(Zhu,2013)and renamed as SCSAM in *** were 90 oral presentations and 57 posters in the meeting this year,which attracted attentions of more than 2000 audiences both on line and on *** short article summaries the cutting-edge advances in interscale and interdisciplinary approaches to the SCS from the meeting presentations and the associated research.

关键词： South Indian marginal

Research on Radar Emitter Attribute Recognition Method

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Geo-Spatial Information Science 2006年第1期9卷 45-48页

作者： guan Xin yi Xiao HE You Naval Aeronautical Engineering Institute 188 Erma Road Yantai 264001 China

In order to solve emitter recognition problems in a practical reconnaissance environment, attribute mathematics is introduced. The basic concepts and theory of attribute set and attribute measure are described i n detail. A new attribute recognition method based on attribute measure is prese nted in this paper. Application example is given, which demonstrates this new me thod is accurate and effective. Moreover, computer simulation for recognizing th e emitter purpose is selected, and compared with classical statistical pattern r ecognition through simulation. The excellent experimental results demonstrate t hat this is a brand-new attribute recognition method as compared to existing st atistical pattern recognition techniques.

关键词： attribute measure attribute recognition criterion emitter recognition

Insulation degradation and fracture cracks of mechanical impacted thermal-ageing oil-impregnated papers

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High Voltage 2023年第1期8卷 21-30页

作者： Minghe Chi Ruochun Xia yi guan Weifeng Sun Ji Liu Qingguo Chen Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationSchool of Electrical and Electronic EngineeringHarbin University of Science and TechnologyHarbinChina School of Electrical and Electronic Engineering Nanyang Technological UniversitySingaporeSingapore

In order to elucidate mechanical impacts affecting the insulation strength of thermalageing oil-impregnated pressboards,we perform mechanical degradation experiments of impacting forces that are represented as the winding-suffered stresses on thermalageing oil-paper insulation in transient short-circuit of *** content,degree of polymerisation(DP),partial discharge inception voltage and AC breakdown field strength are tested and analysed for diverse thermal-ageing *** analytical model of mechanical degradation is established by relating dielectric breakdown strength to mechanical *** impacts result in less water content in thermal-aging oilimpregnated pressboards while causing reduction and increment of DP,respectively,in mildly and severely aged oil-impregnated *** discharge inception voltage and dielectric breakdown strength vary significantly with the numbers of impact cycles,showing a maximum value under low-intensity impact and decreasing monotonously under high-intensity ***-intensity mechanical impacts will evidently exacerbate the thermal deterioration process of oil-impregnated pressboards,which is primarily attributed to cellulose fibre fractures in pressboard cracks produced by equivalent tensile stress of mechanical *** is acceptable for mildly aged oil-impregnated pressboards to suffer low-intensity mechanical impacts that will alleviate insulation degradation by restraining partial discharge in smaller oil-gaps and prolonging breakdown discharge pathways along impact-caused cracks.

关键词： fracture thermal insulation

A seqlet-based maximum entropy Markov approach for protein secondary structure prediction

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Science China(Life Sciences) 2005年第4期48卷 394-405页

作者： DONG Qiwen WANG Xiaolong LIN Lei guan yi School of Computer Science and Technology Harbin Institute of Technology Harbin 150006 China School of Computer Science and Technology Harbin Institute of Technology Harbin 150006 China School of Computer Science and Technology Harbin Institute of Technology Harbin 150006 China School of Computer Science and Technology Harbin Institute of Technology Harbin 150006 China

A novel method for predicting the secondary structures of proteins from amino acid sequence has been presented. The protein secondary structure seqlets that are analogous to the words in natural language have been extracted. These seqlets will capture the relationship be-tween amino acid sequence and the secondary structures of proteins and further form the protein secondary structure dictionary. To be elaborate, the dictionary is organism-specific. Protein sec-ondary structure prediction is formulated as an integrated word segmentation and part of speech tagging problem. The word-lattice is used to represent the results of the word segmentation and the maximum entropy model is used to calculate the probability of a seqlet tagged as a certain secondary structure type. The method is markovian in the seqlets, permitting efficient exact cal-culation of the posterior probability distribution over all possible word segmentations and their tags by viterbi algorithm. The optimal segmentations and their tags are computed as the results of protein secondary structure prediction. The method is applied to predict the secondary struc-tures of proteins of four organisms respectively and compared with the PHD method. The results show that the performance of this method is higher than that of PHD by about 3.9% Q3 accuracy and 4.6% SOV accuracy. Combining with the local similarity protein sequences that are obtained by BLAST can give better prediction. The method is also tested on the 50 CASP5 target proteins with Q3 accuracy 78.9% and SOV accuracy 77.1%. A web server for protein secondary structure prediction has been constructed which is available at http://***:81/demos/bi-ology/***.

关键词： protein secondary structure prediction protein secondary structure seqlets Word-lattice maximum entropy Markov model.

Development and application of marker-assisted reverse breeding using hybrid maize germplasm

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Journal of Integrative Agriculture 2015年第12期14卷 2538-2546页

作者： guan yi-Xin WANG Bao-hua FENG Yan LI Ping Scientific Observing and Experimental Station of Maize in Plain Area of Southern Region Ministry of AgricultureSchool of Life Sciences Nantong University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Nantong Xinhe Bio-Technology Co. Ltd.

Humankind has been through different periods of agricultural improvement aiming at enhancing our food supply and the performance of food crops. In recent years, whole genome sequencing and deep understanding of genetic and epigenetic mechanisms have facilitated new plant breeding approaches to meet the challenge of growing population, dwindling resources, and changing climate. Here we proposed a simple and fast molecular breeding method, marker-assisted reverse breeding（MARB）, which will revert any maize hybrid into inbred lines with any level of required similarity to its original parent lines. Since all the pericarp DNA of a hybrid is from the maternal parent, whereas one half of the embryo DNA is from the maternal parent and the other half from the paternal parent, so we firstly extract DNA from seed embryo and pericarp of a selected elite hybrid separately and then we derived the genotypes of the two parents with high-density single nucleotide polymorphism（SNP） chips. The following marker-assisted selection was performed based on an Illumina low-density SNP chip designed with 192 SNPs polymorphic between the two parental genotypes, which were uniformly distributed on 10 maize chromosomes. This method has the advantages of fast speed, fixed heterotic mode, and quick recovery of beneficial parental genotypes compared to traditional pedigree breeding using elite hybrids. Meanwhile, MARB has the advantage of not requiring sophisticated transformation and double haploid（DH） technologies over RNA interference（RNAi）-mediated reverse breeding. In addition, MARB can also be used with feed corn harvested from big farms, which is often similar to F_2 populations, and the relevant transgenes in the population can be eliminated by marker-assisted selection. As a result, the whole global commercial maize hybrids can be utilized as germplasm for breeding with MARB technology. Starting with an F_2 population derived from an elite hybrid, our experiment indicates that with three

关键词： maize hybrid marker-assisted reverse breeding SNP

The role of Epstein-Barr virus in multiple sclerosis:from molecular pathophysiology to in vivo imaging

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Neural Regeneration Research 2019年第3期14卷 373-386页

作者： yi guan Dejan Jakimovski Murali Ramanathan Bianca Weinstock-Guttman Robert Zivadinov Buffalo Neuroimaging Analysis Center Department of Neurology Jacobs School of Medicine and Biomedical Sciences University at BuffaloState University of New York Jacobs Comprehensive MS Treatment and Research Center Department of Neurology Jacobs School of Medicine and Biomedical SciencesUniversity at Buffalo State University of New York Department of Pharmaceutical Sciences State University of New York Center for Biomedical Imaging at Clinical Translational Science Institute University at Buffalo State University of New York

Multiple sclerosis(MS) is a disease of the central nervous system characterized by inflammation, demyelination, and neuronal damage. Environmental and genetic factors are associated with the risk of developing MS, but the exact cause still remains unidentified. Epstein-Barr virus(EBV), vitamin D, and smoking are among the most well-established environmental risk factors in MS. Infectious mononucleosis, which is caused by delayed primary EBV infection, increases the risk of developing MS. EBV may also contribute to MS pathogenesis indirectly by activating silent human endogenous retrovirus-W. The emerging B-cell depleting therapies, particularly anti-CD20 agents such as rituximab, ocrelizumab, as well as the fully human ofatumumab, have shown promising clinical and magnetic resonance imaging benefit. One potential effect of these therapies is the depletion of memory B-cells, the primary reservoir site where EBV latency occurs. In addition, EBV potentially interacts with both genetic and other environmental factors to increase susceptibility and disease severity of MS. This review examines the role of EBV in MS pathophysiology and summarizes the recent clinical and radiological findings, with a focus on B-cells and in vivo imaging. Addressing the potential link between EBV and MS allows the better understanding of MS pathogenesis and helps to identify additional disease biomarkers that may be responsive to B-cell depleting intervention.

关键词： Epstein-Barr virus multiple sclerosis meningeal inflammation magnetic resonance imaging leptomeningeal contrast enhancement mononucleosis human endogeneous retrovirus-W B-cells

Synthesis, Crystal Structure and Theoretically Study of 2-(Dimethylamino)-1,3-dithiocyanatopropane and Its Isomer

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Chemical Research in Chinese Universities 2011年第6期27卷 963-967页

作者： YU guan-ping MA yi LIU Zhuo WANG Gang LI Zheng-ming State Key Laboratory of Elemento-organic Chemistry Research Institute of Elemento-organic Chemistry Nankai University Tianjin 300071 P. R. China

2-（Dimethylamino）-1,3-dithiocyanatopropane（1） has been prepared as a key intermediate synthesizing a natural insecticide Cartap by the reaction of 1-dimethylamino-2,3-dichloropropane with sodium thiocyanate. The crystal structures of compound 1 and its isomer 1-（dimethylamino）-2,3-dithiocyanotopropane（2） formed during the reaction were determined by X-ray single-crystal diffraction. Bond lengths in both the compounds are common and fall within normal ranges. There are some weak C―H×××N hydrogen bonds in the lattice of compound 1, which makes it form a three-dimensional network, which stabilize the crystal structure. No classic hydrogen bonds were founded in its isomer（2）, only van der Waals forces contribute to the stability of the structure. In addition, DFT and MP2 calculations with 6-311＋G（d, p） basis set have also been carried out to investigate the thermodynamic properties of compounds 1 and 2. The research will be applied to the further investigation of the tautomerization of compounds 1 and 2.

关键词： Cartap Crystal structure Theoretical calculation Thermodynamic property

Characterization of astrocytes and microglial cells in the hippocampal CA1 region after transient focal cerebral ischemia in rats treated with Ilexonin A

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Neural Regeneration Research 2020年第1期15卷 78-85页

作者： Ai-Ling Xu guan-yi Zheng Hui-ying Ye Xiao-Dong Chen Qiong Jiang Department of Traditional Chinese Medicine Fujian Medical University Union HospitalFuzhouFujian ProvinceChina Department of Neonatology People’s Hospital Affiliated to Fujian University of Traditional Chinese MedicineFuzhouFujian ProvinceChina Department of Neurology People’s Hospital of NanpingNanpingFujian ProvinceChina Burns Institute of Fujian Medical University Union Hospital FuzhouFujian ProvinceChina

Ilexonin A is a compound isolated from the root of Ilex pubescens,a traditional Chinese *** A has been shown to play a neuroprotective role by regulating the activation of astrocytes and microglia in the peri-infarct area after ***,the effects of ilexonin A on astrocytes and microglia in the infarct-free region of the hippocampal CA1 region remain *** cerebral ischemia models were established by 2-hour occlusion of the middle cerebral artery in *** A(20,40 or 80 mg/kg)was administered immediately after ischemia/*** astrocyte marker glial fibrillary acidic protein,microglia marker Iba-1,neural stem cell marker nestin and inflammation markers were detected by immunohistochemistry and western blot *** levels of tumor necrosis factor-αand interleukin 1βwere determined by enzyme linked immunosorbent assay in the hippocampal CA1 *** were activated immediately in progressively increasing numbers from 1,3,to 7 days post-ischemia/*** number of activated astrocytes further increased in the hippocampal CA1 region after treatment with ilexonin *** cells remained quiescent after ischemia/reperfusion,but became activated after treatment with ilexonin *** A enhanced nestin expression and reduced the expression of tumor necrosis factor-αand interleukin 1βin the hippocampus post-ischemia/*** results of the present study suggest that ilexonin A has a neuroprotective effect in the hippocampus after ischemia/reperfusion,probably through regulating astrocytes and microglia activation,promoting neuronal stem cell proliferation and reducing the levels of pro-inflammatory *** study was approved by the Animal Ethics Committee of the Fujian Medical University Union Hospital,China.

关键词： astrocytes hippocampal CA1 region ilexonin A microglia middle cerebral artery occlusion neural stem cell neuroprotection transient focal cerebral ischemia