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Nano-sized alumina supported palladium catalysts for methane combustion with excellent thermal stability

Journal of Environmental Sciences 2023年第4期126卷 333-347页

作者： Wei shi Guangyan Xu Xuewang Han Yingjie Wang Zhi Liu Sen Xue nannan Sun Xiaoyan shi Yunbo Yu Hong He State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Weichai Power Co. Ltd.Weifang 261061China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

Pd/Al_(2)O_(3)catalysts supported on Al_(2)O_(3)of different particle sizes were synthesized and applied in methane combustion.These catalysts were systematically characterized by Brunauer-Emmett-Teller (BET),X-ray diffraction (XRD),high resolution-transmission electron microscopy (HR-TEM),high-angle annular dark?eld-scanning transmission electron microscopy (HAADF-STEM),H_(2)-temperature-programmed reduction (H_(2)-TPR),O_(2)-temperature-programmed oxidation (O_(2)-TPO),X-ray photoelectron spectroscopy (XPS),and X-ray absorption?ne structure (XAFS).The characterization results indicated that nanosized Al_(2)O_(3)enabled the uniform dispersion of palladium nanoparticles,thus contributing to the excellent catalytic performance of these nano-sized Pd/Al_(2)O_(3)catalysts.Among them,Pd/Al_(2)O_(3)-nano-10 (Pd/Al_(2)O_(3)supported by alumina with an average particle size of 10 nm)showed superior catalytic activity and stability for methane oxidation under harsh practical conditions.It maintained excellent catalytic performance for methane oxidation for50 hr and remained stable even after harsh hydrothermal aging in 10 vol.%steam at 800℃ for 16 hr.Characterization results revealed that the strong metal-support interactions and physical barriers provided by Al_(2)O_(3)-nano-10 suppressed the coalescence ripening of palladium species,and thus contributed to the superior sintering resistance of the Pd/Al_(2)O_(3)-nano-10 catalyst.

关键词： Methane combustion Pd/Al_(2)O_(3) Hydrothermal stability Metal-support interaction Physical barriers

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AMPK-ChREBP axis mediates de novo milk fatty acid synthesis promoted by glucose in the mammary gland of lactating goats

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Animal Nutrition 2022年第3期10卷 234-242页

作者： Hengbo shi nannan Jiang Ling Wei Jie Cai Wenying Zhang Qianming Jiang Juan JLoor Jianxin Liu Institute of Dairy Science College of Animal SciencesZhejiang UniversityHangzhou310058China College of Life Sciences and Medicine Zhejiang Sci-Tech UniversityHangzhou310018China Mammalian Nutrition Physiology Genomics Department of Animal Sciences and Division of Nutritional SciencesUniversity of IllinoisUrbanaIL61801USA

To investigate the role of glucose in regulating milk fatty acid synthesis,6 lactating Guanzhong dairy goats were infused with 0,60,or 100 g/d glucose via the external pubic artery in a 33 repeated Latin square experiment.A concomitant in vitro experiment was conducted to investigate possible mechanisms whereby glucose regulates milk fatty acid synthesis.RNA sequencing was used for cellular transcriptome analysis.Drugs,MK-2206,rapamycin,and dorsomorphin were used to block cellular mammalian AMP-activated protein kinase(AMPK),AKT serine/threonine kinase 1,and mechanistic target of rapamycin kinase signaling pathways,respectively.Carbohydrate response element binding protein(ChREBP)was knockdown and overexpressed to investigate its role in regulating milk fatty acid synthesis in mammary epithelial cells.Glucose infusion linearly elevated the concentration of C8:0(P=0.039)and C10:0(P=0.041)in milk fat while it linearly decreased(P=0.049)that of C16:0.This result was in agreement with the upregulation of genes related to de novo synthesis of fatty acids and lipid droplet formation,including adipose differentiation-related protein,butyrophilin subfamily 1 member A1,fatty acid synthase(FASN)and ChREBP.Their expression increased(P<0.05)linearly in the lactating goat mammary gland.In vitro,glucose linearly stimulated the expression of genes related to de novo synthesis of fatty acids and cellular triacylglycerol in cultured mammary epithelial cells.RNA sequencing and inhibition studies revealed that glucose induced transcriptomic changes increasing lipogenic pathways,with AMPK responding to glucose by controlling ChREBP and FASN.Knockdown and overexpression of ChREBP highlighted its essential role in lipogenesis.The knockdown and overexpression of ChREBP protein also revealed an essential role in regulating the de novo synthesis of fatty acids.Collectively,our data highlight that glucose supplementation promotes de novo fatty acid synthesis via the AMPK-ChREBP axis,hence increasing milk fat yield in the goat mammary gla

关键词： Milk fat Glucose infusion Mammary gland Carbohydrate response element binding protein De novo synthesis

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Diagnostic Value of Neutrophil-Lymphocyte Ratio and Platelet-Lymphocyte Ratio in Patients with Severe COVID-19—7 PLADs,China,January 21–February 10,2020

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China CDC weekly 2022年第10期4卷 195-198,I0001页

作者： Yan Ma Dongshan Zhu Nannan Shi Lei Zhang Guangkun Chen Youwen Ge Zelei Zhang Renbo Chen Sihong Liu Yipin Fan Huamin Zhang Yanping Wang Department of Infectious Disease Prevention Institute of Basic Research in Clinical MedicineChina Academy of Chinese Medical SciencesBeijingChina Department of Epidemiology School of Public HealthCheeloo College of MedicineShandong UniversityJinanShandong ProvinceChina Jinan250012China Chinese Medicine Standardization Research Center Institute of Basic Research in Clinical MedicineChina Academy of Chinese Medical SciencesBeijingChina Institute of Information on Traditional Chinese Medicine China Academy of Chinese Medical SciencesBeijingChina Institute of Chinese Materia Medica China Academy of Chinese Medical SciencesBeijingChina.

Summary What is already known about this topic?Coronavirus disease 2019(COVID-19)causes symptoms ranging from mild to severe.Indicators for identifying severe COVID-19 infection have not been well identified,especially for young patients.What is added by this report?Both neutrophil-lymphocyte ratio(NLR)[area under curve(AUC):0.80;the odds ratios(OR)and 95%confidence intervals(95%CI):1.30(1.13–1.50)]and platelet-lymphocyte ratio(PLR)[AUC:0.87;OR(95%CI):1.05(1.01–1.09)]were determined to be indicators for recognition of patients with severe COVID-19 in young patients less than age 40.What are the implications for public health practice?NLR and PLR are useful indicators for identifying patients with severe COVID-19,especially in young patients less than age 40.

关键词： Lymphocyte Patients Platelet

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Promoting nitric oxide electroreduction to ammonia over electron-rich Cu modulated by Ru doping

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Science China Chemistry 2021年第9期64卷 1493-1497页

作者： Jiangwei shi Changhong Wang Rong Yang Fanpeng Chen nannan Meng Yifu Yu Bin Zhang Department of Catalysis Science and Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China Institute of Molecular Plus School of ScienceTianjin UniversityTianjin300072China

Electrocatalytic nitric oxide(NO)reduction is a promising strategy to produce ammonia.Developing a facile approach to synthesize efficient catalysts with enhanced NO electroreduction performance is highly desirable.Here,a series of Ru-doped Cu materials are constructed through in situ electroreduction of corresponding metal hydroxides.The optimized Ru_(0.05)Cu_(0.95)exhibits superior electrocatalytic performance for ammonia synthesis by using NO/Ar(1/4,n/n)as the feedstocks(Faradaic efficiency:64.9%,yield rate:17.68μmol cm^(-2)h^(-1)),obviously outperforming Cu counterpart(Faradaic efficiency:33.0%,yield rate:5.73μmol cm^(-2)h^(-1)).Electrochemical in situ Fourier transform infrared(FTIR)spectroscopy and online differential electrochemical mass spectrometry(DEMS)are adopted to detect intermediates and unveil the possible reaction pathway.The downshift of the Cu d-band center induced by Ru doping facilitates the rate-limiting hydrogenation step and decreases the desorption energy of NH_(3),leading to high Faradaic efficiency and yield of ammonia.

关键词： Electrocatalysis NO ammonia synthesis in situ characterizations Ru-doped Cu

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Distortion Function for Emoji Image Steganography

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Computers, Materials & Continua 2019年第6期59卷 943-953页

作者： Lina shi Zichi Wang Zhenxing Qian nannan Huang Pauline Puteaux Xinpeng Zhang Shanghai Institute for Advanced Communication and Data Science School of Communication and Information EngineeringShanghai UniversityShanghai200444China Laboratoire d'Informatique de Robotique et de Microlectronique de MontpellierCentre National de la Recherche ScientifiqueUniversity of MontpellierMontpellier34095France

Nowadays,emoji image is widely used in social networks.To achieve covert communication in emoji images,this paper proposes a distortion function for emoji images steganography.The profile of image content,the intra-and inter-frame correlation are taken into account in the proposed distortion function to fit the unique properties of emoji image.The three parts are combined together to measure the risks of detection due to the modification on the cover data.With the popular syndrome trellis coding(STC),the distortion of stego emoji image is minimized using the proposed distortion function.As a result,less detectable artifacts could be found in the stego images.Experimental results show that the proposed distortion function performs much higher undetectability than current state-of-the-art distortion function HILL which is designed for natural image.

关键词： Steganography emoji image distortion function

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Early identification of acute hypoxia based on brain NADH fluores cence and cerebral blood flow

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Journal of Innovative Optical Health Sciences 2014年第2期7卷 153-161页

作者： Hua shi nannan Sun Avraham Mayevsky Zhihong Zhang Qingning Luo Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for Optoelectronics-Huazhong University of Scienceand Technology Wuhan 430074 P.R.China MoE Key Laboratory for Biomedical Photonics Department of Biomedical Engineering Huazhong University of Science and Technology(HUST)Wuhan 430074P.R.China

Hypoxia is closely related to many diseases and often leads to death.Early detection andidentification of the hypoxia causes may help to promptly determine the right rescue plan andreduce the mortality.We proposed a new multiparametric monitoring method employingmitochondrial reduced nicotinamide adenine dinucleotide(NA DH)fluorescence,regional reflectance,regional cerebral blood flow(CBF),electrocardiography(ECG),and respiration under sixkinds of acute hypoxia in four categories to investigate a correlation bet ween the parametervariances and the hypoxia causes.The variation patterns of the paramet ers were discussed,andthe combination of NADH and CBF may contribute to the identification of the causes of hypoxia.

关键词： Nicotinamide adenine dinucleotide fuorescence acute hypoxia carly detection cer-ebral blood flow.

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Carbazole-endcapped Spiro[fluorene-9,9＇-xanthene] with Large Steric Hindrance as Hole-transporting Host for Heavily-doped and High Performance OLEDs

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Chinese Journal of Chemistry 2015年第8期33卷 955-960页

作者： Xianghua Zhao Yukun Wu Nannan Shi Xiaoyu Li Yi Zhao Mingli Sun Dongxue Ding Hui Xu Linghai Xie College of Chemistry and Chemical Engineering Xinyang Normal University Xinyang Henan 464000 China State Key Laboratory on Integrated Optoelectronics College of Electronics Science and Engineering Jilin University 2699 Qianjin Street Changchun Jilin 130012 China China Key Laboratory for Organic Electronics & Information Displays (KLOEID) Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications Nanjing Jiangsu 210046 China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education Heilongjiang University Harbin Heilongjiang 150080 China

In this work, we designed and synthesized a novel spirocyclic compound functionalized spiro[fluorene-9,9＇- xanthene] with carbazole group （2-carbazolyl-spiro[fluorene-9,9＇-xanthene], SFX-Cz） via Friedel-Crafts and Ullmann reaction, which is expected to own high thermal and morphological stability, and good carrier injection/ transporting properties due to the excellent hole transporting characteristics of carbazole and cruciform structure of spiro[fluorene-9,9＇-xanthene]. The carbazole end-capped spiro[fluorene-9,9＇-xanthene] SFX-Cz based PhOLEDs with Flrpic as phosphor emitter have been researched by varying dopant concentration, which exhibit the maximum EQEs of 8.9%, 7.4%, 9.1%, and 4.7% with the doping increasing from 10% to 50%. The higher performance PhOLEDs are independent on concentration variation from 10% to 30%, which suggests the bulky steric hindrance of SFX-Cz might be a potential canditate for high performance and inexpensive device with simplified process.

关键词： steric hindrance spirocyclic compound heavily-doped PhOLEDs inexpensive device

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Investigation of Electrical Parameters of Fresh Water and Produced Mixed Injection in High-Salinity Reservoirs

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Fluid Dynamics & Materials Processing 2023年第10期19卷 2695-2706页

作者： Jun Li Guofeng Cheng Hongwei Xiao Xiang Li Lizhi Wang Hui Xu Yu Wang nannan Liu Shangping Chen Xing shi PetroChina Research Institute of Petroleum Exploration&Development Beijing100083China Changqing Oilfield No.5 Oil Production Plant PetroChinaXi’an710000China Exploration and Development Research Institute of Daqing Oilfield Co. Ltd.Daqing163712China Key Laboratory of Shallow Geothermal Energy Ministry of Natural Resources of the People’s Republic of ChinaBeijing100195China Jiangsu Key Laboratory of Oil-Gas Storage and Transportation Technology School of Petroleum and Natural Gas EngineeringChangzhou UniversityChangzhou213164China Sinopec International Petroleum Exploration and Production Corporation Beijing100029China

Assuming a reservoir with a typical salt-lake background in the Qaidam Basin as a testbed,in this study the var-iation law of the rock electrical parameters has been determined through water displacement experiments with different salinities.As made evident by the results,the saturation index increases with the degree of water injec-tion.When the salinity of the injected water is lower than 80000 ppm,the resistivity of the rock sampleﬁrst decreases,then it remains almost constant in an intermediate stage,andﬁnally it grows,thereby giving rise to a‘U’proﬁle behavior.As the salinity decreases,the water saturation corresponding to the inﬂection point of the resistivity becomes lower,thereby leading to a wider‘U’type range and a higher terminal resistivity.For dif-ferent samples,higher initial resistivity of the sample in the oil-bearing state,and higher resistivity after low-sali-nity water washing are obtained when a thicker lithology is considered.

关键词： High salinity reservoir mixed injection saturation index resistivity electrical parameters

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Frontiers of CO_(2)Capture and Utilization(CCU)towards Carbon Neutrality

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Advances in Atmospheric Sciences 2022年第8期39卷 1252-1270页

作者： Lingyun ZHANG Yanfang SONG Jialin shi Qun SHEN Deng HU Qiang GAO Wei CHEN Kien-Woh KOW Chengheng PANG nannan SUN Wei WEI CAS Key Laboratory of Low-Carbon Conversion Science&Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China Department of Chemical and Environmental Engineering Faculty of Science and EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100China Key Laboratory for Carbonaceous Wastes Processing and Process Intensification Research of Zhejiang Province University of Nottingham Ningbo ChinaNingbo 315100China New Materials Institute the University of Nottingham Ningbo ChinaNingbo 315100China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

CO_(2)capture,utilization,and storage(CCUS)technology is a rare option for the large-scale use of fossil fuels in a low-carbon way,which will definitely play a part in the journey towards carbon neutrality.Within the CCUS nexus,CCU is especially interesting because these processes will establish a new“atmosphere-to-atmosphere”carbon cycle and thus indirectly offer huge potential in carbon reduction.This study focuses on the new positioning of CCUS in the carbon neutrality scenario and aims to identify potential cutting-edge/disruptive CCU technologies that may find important application opportunities during the decarbonization of the energy and industrial system.To this end,direct air capture(DAC),flexible metal-framework materials(MOFs)for CO_(2)capture,integrated CO_(2)capture and conversion(ICCC),and electrocatalytic CO_(2)reduction(ECR)were selected,and their general introduction,the importance to carbon neutrality,and most up-to-date research progress are summarized.

关键词： carbon neutrality carbon reduction decarbonization CO_(2) CCU

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Molten salt as ultrastrong polar solvent enables the most straightforward pyrolysis towards highly efficient and stable single-atom electrocatalyst

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Journal of Energy Chemistry 2021年第3期30卷 519-527页

作者： nannan Li Wei Liu Chao Zhu Ce Hao Jingya Guo Hongyu Jing Jinwen Hu Cuncun Xin Danyang Wu Yantao shi State Key Laboratory of Fine Chemicals Department of ChemistrySchool of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of EducationCollaborative Innovation Center for Micro/Nano FabricationDevice and SystemSoutheast University2 No.4 PailouNanjing 210096JiangsuChina

Currently,pyrolysis as the most widely used method still has some key issues not well resolved for synthesis of carbon-supported single-atom catalysts(C-SACs),e.g.,the sintering of metal atoms at high temperature as well as the high cost and complicated preparations of precursors.In this report,molten salts are demonstrated to be marvellous medium for preparation of C-SACs by pyrolysis of small molecular precursors(ionic liquid).The ultrastrong polarity on one hand establishes robust interaction with precursor and enables better carbonization,resulting in largely enhanced yield.On the other hand,the aggregation of metal atoms is effectively refrained while no nanoparticle or cluster is formed.By this strategy,a C-SAC with atomically dispersed Fe-N_(4) sites and a high specific area over 2000 m^(2) g^(-1) is obtained,which illustrates high ORR activity in both acid and alkaline media.Moreover,this SAC exhibits superior methanol tolerance and stability after acid soaking at 85℃ for 48 h.It is believed that the molten-salts-assisted pyrolysis can be developed into a routine strategy as it not only can largely simply the synthesis of C-SACs,but also can be extended to prepare other types of SACs.

关键词： Ultrastrong polar solvent Molten salts one-pot pyrolysis Carbon-supported single atom catalysts Oxygen reduction reaction

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