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Effects of zinc on χ-Fe_(5)C_(2) for carbon dioxide hydrogenation to olefins:Insights from experimental and density function theory calculations

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Chinese Journal of Chemical Engineering 2023年第2期54卷 206-214页

作者： xianglin liu Minjie Xu Chenxi Cao Zixu Yang Jing Xu State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Maoming Branch R&D Institute SINOPECMaoming 525000China Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

Production of light olefins from CO_(2), the primary greenhouse gases, is of great importance to mitigate the adverse effects of CO_(2) emission on environment and to supply the value-added products from nonpetroleum resource. However, development of robust catalyst with controllable selectivity and stability remains a challenge. Herein, we report that Zn-promoted Fe catalyst can boost the stable and selective production of light olefins from CO_(2). Specifically, the Zn-promoted Fe exhibits a highly stable activity and olefin selectivity over 200 h time-on-stream compared to the unpromoted Fe catalyst, primarily owing to the preservation of active χ-Fe_(5)C_(2) phase. Structural characterizations of the spent catalysts suggest that Zn substantially regulates the content of iron carbide on the surface and suppresses the reoxidation of bulk iron carbide during the reaction. DFT calculations confirm that adsorption of surface carbon atoms and graphene-like carbonaceous species are not thermochemically favored on Zn-promoted Fe catalyst. Carbon deposition by CAC coupling reactions of two surface carbon atoms and dehydrogenation of CH intermediate are also inhibited. Furthermore, the effects of Zn on antioxidation of iron carbide were also investigated. Zn favored the hydrogenation of surface adsorbed oxygen atoms to H_(2)O and the desorption of H_(2)O, which reduces the possibility of surface carbide being oxidized by the chemisorbed oxygen.

关键词： Reaction engineering χ-Fe_(5)C_(2) Zn promoter Carbon dioxide Hydrogenation Density function theory

Quality assessment of onboard GPS receiver and its combination with DORIS and SLR for Haiyang 2A precise orbit determination

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Science China Earth Sciences 2015年第1期58卷 138-150页

作者： GUO Jing ZHAO QiLe GUO Xiang liu xianglin liu JingNan ZHOU Quan GNSS Research Center Wuhan University School of Geodesy and Geomatics Wuhan University Fugro Intersite B.V. Leidschendam 2263HWNetherlands Collaborative Innovation Center of Earth and Space Science Wuhan University Test and Assessment Research Center China Satellite Navigation Office

The GPS,DORIS,and SLR instruments are installed on Haiyang 2A(HY2A)altimetry satellite for Precise Orbit Determination(POD).Among these instruments,the codeless GPS receiver is the state-of-art Chinese indigenous onboard receiver,and it is the first one successfully used for Low Earth Orbit(LEO)***,the contribution assesses the performance of the receiver through an analysis of data integrity,numbers of all tracked and valid measurements as well as multipath *** receiver generally shows good performance and quality despite a few *** example,L2 observations are often missing in low elevations,particularly during the ascent of GPS satellites,and the multipath errors of P1 show a slightly abnormal ***,the PCO(Phase Center Offset)and PCV(Phase Center Variation)of the antenna of the GPS receiver are determined in this contribution.A significant leap for Z-component of PCO up to-1.2 cm has been found on 10 October ***,the obtained PCO and PCV maps are used for GPS only POD *** post-fit residuals of ionosphere-free phase combinations reduce almost 50%,and the radial orbit differences with respect to CNES(Centre National d’Etudes Spatiales)Precise Orbit Ephemeris(POEs)improve about 13.9%.The orbits are validated using the SLR data,and the RMS of SLR Observed minus Computed(O-C)residuals reduces from 17.5 to 15.9 *** improvements are with respect to the orbits determined without PCO and ***,six types of solutions are determined for HY2A satellite using different combinations of GPS,DORIS,and SLR *** of SLR O-C residuals and cross-comparison of orbits obtained in the contribution and the CNES POEs indicate that the radial accuracy of these orbits is at the 1.0 cm level for HY2A orbit solutions,which is much better than the scientific requirements of this *** is noticed that the GPS observations dominate the achievable accuracy of POD,and the combination of multiple types of observation

关键词： Haiyang 2A GPS receiver multipath precise orbit determination phase center offset phase center variations DORIS SLR

Transfer of a eubacteria-type cell division site-determining factor CrMinD gene to the nucleus from the chloroplast genome in Chlamydomonas reinhardtii

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Chinese Science Bulletin 2007年第18期52卷 2514-2521页

作者： liu WeiZhong HU Yong ZHANG RunJie ZHOU WeiWei ZHU JiaYing liu xianglin HE YiKun College of Life Science Capital Normal University Beijing 100037 China College of Life Science Shanxi Normal University Linfen 041004 China College of Life Science Shanxi Normal University Linfen 041004 China

MinD is a ubiquitous ATPase that plays a crucial role in selection of the division site in eubacteria, chloroplasts, and probably Archaea. In four green algae, Mesostigma viride, Nephroselmis olivacea, Chlorella vulgaris and Prototheca wickerhamii, MinD homologues are encoded in the plastid genome. However, in Arabidopsis, MinD is a nucleus-encoded, chloroplast-targeted protein involved in chloro- plast division, which suggests that MinD has been transferred to the nucleus in higher land plants. Yet the lateral gene transfer (LGT) of MinD from plastid to nucleus during plastid evolution remains poorly understood. Here, we identified a nucleus-encoded MinD homologue from unicellular green alga Chlamydomonas reinhardtii, a basal species in the green plant lineage. Overexpression of CrMinD in wild type E. coli inhibited cell division and resulted in the filamentous cell formation, clearly demon- strated the conservation of the MinD protein during the evolution of photosynthetic eukaryotes. The transient expression of CrMinD-egfp confirmed the role of CrMinD protein in the regulation of plastid division. Searching all the published plastid genomic sequences of land plants, no MinD homologues were found, which suggests that the transfer of MinD from plastid to nucleus might have occurred be- fore the evolution of land plants.

关键词：衣藻叶绿体 CrMinD基因基因转移植物进化

Water storage variations of the Yangtze,Yellow,and Zhujiang river basins derived from the DEOS Mass Transport (DMT-1) model

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Science China Earth Sciences 2011年第5期54卷 667-677页

作者： ZHAO QiLe liu xianglin Pavel DITMAR Christian SIEMES Elena REVTOVA Hassan HASHEMI-FARAHANI Roland KLEES Delft Institute of Earth Observation and Space Systems (DEOS) Faculty of Aerospace Engineering Delft University of Technology Kluverweg 1 2629 HS Delft the Netherlands GNSS Research Center Wuhan University Wuhan 430079 China

In general, China is short of water resources and some regions even experience a shortage of daily water supply. This could threaten the stability and economic development of the nation. A study on the water storage variations is especially important for the water management and storage prediction in three largest river basins of China, namely, Yangtze, Yellow, and Zhujiang, where the most dense population and leading economic regions are located. The satellite gravity mission GRACE （Gravity Recovery and Climate Experiment） provides an opportunity to macroseopically identify water （or mass） variations in the Earth＇s system with a spatial resolution of 300-400 km and a temporal resolution of about one month. We use the first release of the DEOS （Delft Institute of Earth Observation and Space Systems） Mass Transport （DMT-1） model based on GRACE data to analyze water storage changes in the three river basins. The DMT-1 model consists of monthly solutions, which are computed using an innovative methodology. The methodology includes, in particular, the application of a statistically optimal Wiener-type filter based on full varianee-covariance matrices of noise and signal. This results in particularly sharp mass variation maps. Taking one monthly solution as an example, we compare the results derived from the DMT-1 model with ones produced with the standard post-processing scheme based on a combination of the de-striping and Gaussian filtering. The comparison shows that the DMT-1 model outperforms the other models and is suitable for the analysis of the mass changes in river basins. A subset of the DMT-1 solutions in the interval between February 2003 and May 2008 is used to estimate the secular trends and seasonal variations for the three river basins. The estimated trends show that the water storage of the Yellow River basin does not have significant changes, while the Zhujiang and Yangtze river basins have a large and statistically significant water storage increase. T

关键词： GRACE DMT-1 water storage variation equivalent water layer thickness Yangtze-Yeilow-Zhujiang river basins secular and seasonal variation

Toxic effects of three perfluorinated or polyfluorinated compounds(PFCs)on two strains of freshwater algae:Implications for ecological risk assessments

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Journal of Environmental Sciences 2023年第9期131卷 48-58页

作者： Liangliang Zhang Xiaowei Zheng xianglin liu Jue Li Yanyao Li Zeming Wang Nan Zheng Xiangrong Wang Zhengqiu Fan Department of Environmental Science and Engineering Fudan UniversityShanghai 200433China Laboratory of Industrial Water and Ecotechnology Department of Green Chemistry and TechnologyGhent UniversityKortrijk 8500Belgium Jinan Environmental Research Academy Jinan 250102China

Perfluorinated or polyfluorinated compounds(PFCs)continue entering to the environmental as individuals or mixtures,but their toxicological information remains largely ***,we investigated the toxic effects and ecological risks of Perfluorooctane sulfonic acid(PFOS)and its substitutes on prokaryotes(Chlorella vulgaris)and eukaryotes(Microcystis aeruginosa).Based on the calculated EC50 values,the results showed that PFOS was significantly more toxic to both algae than its alternatives including Perfluorobutane sulfonic acid(PFBS)and 6:2 Fluoromodulated sulfonates(6:2 FTS),and the PFOS-PFBS mixture was more toxic to both algae than the other two PFC *** action mode of binary PFC mixtures on Chlorella vulgaris was mainly shown as antagonistic and on Microcystis aeruginosa as synergistic,by using Combination index(CI)model coupled with Monte Carlo *** mean risk quotient(RQ)value of three individual PFCs and their mixtures were all below the threshold of 10^(−1),but the risk of those binary mixtures were higher than that of PFCs individually because of their synergistic *** findings contribute to enhance the understanding of the toxicological information and ecological risks of emerging PFCs and provide a scientific basis for their pollution control.

关键词： Toxicity Combination index model Monte Carlo simulation Action mode Algae

In-situ growth of heterophase Ni nanocrystals on graphene for enhanced catalytic reduction of 4-nitrophenol

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Nano Research 2022年第2期15卷 1230-1237页

作者： Jiahao Zhuang Feng He xianglin liu Pengchao Si Fangna Gu Jing Xu Yu Wang Guangwen Xu Ziyi Zhong Fabing Su School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Key Laboratory on Resources Chemicals and Materials of Ministry of Education Shenyang University of Chemical TechnologyShenyang 110142China State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Department of Chemical Engineering Guangdong Technion-Israel Institute of Technology(GTIIT)Shantou 515063China Technion-Israel Institute of Technology(IIT) Haifa 32000Israel

Generating heterophase structures in nanomaterials,e.g.,heterophase metal nanocrystals,is an effective way to tune their physicochemical properties because of their high-energy nature and unique electronic environment of the generated ***,the direct synthesis of heterophase metal nanocrystals remains a great challenge due to their unstable ***,we report the in situar direct synthesis of heterophase Ni nanocrystals on *** heterostructure of face-centered cubic(fee)and hexagonal close-packed(hep)phase was generated via the epitaxial growth of hep Ni and the partial transformation of fee Ni and stabilized by the anchoring effect of graphene toward fee Ni nanocrystal and the preferential adsorption of surfactant polyethylenimine(PEI)toward epitaxial hep *** with the fee Ni nanocrystals grown on graphene,the heterophase(fcc/hcp)Ni nanocrystals in situ grown on graphene showed a greatly improved catalytic activity and reusability in 4-nitrophenol(4-NP)reduction to 4-aminophenol(4-AP).The measured apparent rate constant and the activity parameter were 2.958 min^(-1) and 102 min^(-1)·mg^(-1),respectively,higher than that of the best reported non-noble metal catalysts and most noble metal *** control experiments and density functional theory calculations reveal that the interface of the fee and hep phases enhances the adsorption of substrate 4-NP and thus facilitates the reaction *** work proves the novel idea for the rational design of heterophase metal nanocrystals by employing the synergistic effect of surfactant and support,and also the potential of creating the heterostructure for enhancing their catalytic reactivity.

关键词： heterophase structure Ni nanocrystals graphene 4-nitrophenol(4-NP)reduction catalysts

Construction of cDNA library from iron-deficiency induced maize roots and screening and identification of iron-stress gene Fdr3

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Chinese Science Bulletin 2000年第12期45卷 1127-1131页

作者： YIN Liping QI Xiaoting liu xianglin HUO Chunyan BAI Yanxia QIU Zesheng ZHANG Fusuo Department of Biology Capital Normal UniversityBeijing 100037China China Agricultural University Beijing 100094China

To isolate Fe-deficient related (Fdr) genes, an expression cDNA library of 4.5×105 pfu/μg has been constructed from maize roots in iron-stress. 6 clones have been screened from the cDNA library by differential hybridization screening. It is proved that an Fdr3 cDNA clone expressed stronger under iron-deficient condition than under iron-sufficient one by Northern blot and Western blot.

关键词： maize iron-deficient cDNA library differential hybridization screening iron-deficient related (fdr) clone.

The late Paleoproterozoic extension event:aulacogens and dyke Swarms in the North China craton

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Progress in Natural Science:Materials International 2006年第2期16卷 201-208页

作者： HOU Guiting, LI Jianghai, liu Yulin and QIAN xianglin (Key Laboratory of Orogenic Belts and Crustal Evolution, School of Earth and Space Sciences, Peking University, Beijing 100871, China) [a]Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space Sciences Peking University Beijing China

The extension structures and tectonic implication in the North China Craton ( NCC) are discussed in this paper based on the mafic dyke swarms and geochronology, combining with the geochronology of aulacogens. The late Paleoproterozoic time is the important turning point in the Precambrian evolution of the NCC. The extension system (e.g. aulacogens and dyke swarms) is widespread in the NCC, which marks the carbonization of the NCC with the rigid characteristic similar to the modern plate. The paleostress field modeling suggests that the dyke swarms and aulacogens are arogenic extension marking the start of the supercontinent, not synorogenic and post-orogenic extension. The mafic dyke swarms in the NCC mainly ranged from 1.83 to 1.77 Ga. The extension of the NCC is very limited brittle extension, the average extension ratio is only 0.35% given by mafic dyke swarms extension calculation, so most of extension in the NCC is contributed by the aulacogens. The mafic dyke swarms are related with the aulacogens in the origin.

关键词： North China craton late Paleoproterozoic aulacogens mafic dyke swarms extension.

Cis-regulatory element-based genome-wide identification of DREB1/CBF targets in Arabidopsis

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Progress in Natural Science:Materials International 2008年第5期18卷 579-583页

作者： Huan Zhao a, Weizhong liu a,b, Yong Hu a, xianglin liu a, Yikun He a, a College of Life Science, Capital Normal University, Beijing 100037, China b College of Life Sciences, Shanxi Normal University, Linfen 041004, China College of Life Science Capital Normal University Beijing 100037 China College of Life Sciences Shanxi Normal University Linfen 041004 China

Microarray analysis is used to identify transcriptional targets. However, the direct targets of transcription factors cannot be distin- guished from indirect ones; further, genes with low-expression levels cannot be identi ed by this method. In the present study, we exploit the cis-element dehydration-responsive element (DRE) that is known to be responsible for the transcription of DRE binding factor 1 (DREB1) targets in the promoter region of all Arabidopsis genes. Putative targets whose promoters contain the elements were veri ed by both microarray and reverse transcription-polymerase chain reaction (RT-PCR) analysis. Five new DREB1/CBF direct targets were identi ed. Compared with traditional microarray analysis, our method is convenient and cost-e ective for identifying the downstream targets of transcription factors.

关键词： Arabidopsis Cis-element Transcription factor DREB1/CBF Stress