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Science Bulletin 2019年第1期64卷 36-43页

作者： Bin e Lingzheng Bu Qi Shao Yujing Li Xiaoqing Huang College of Chemistry Chemical Engineering and Materials Science Soochow University Department of Materials Science and engineering China University of Petroleum College of Materials Beijing Institute of Technology

The water-gas shift(WGS) reaction is an essential industrial reaction for upgrading hydrogen(H2) by removing carbon monoxide(CO), while highly efficient platinum(Pt)-based catalysts for WGS with simultaneously high activity and stability are still yet to be developed due to the poisoning issue during the reaction. Herein, we report on the porous PtPb peanut nanocrystals(porous PtPb PNCs) and porous PtPb octahedron nanocrystals(porous PtPb ONCs) with controllable ratios of Pt/Pb as extremely active and stable catalysts towards WGS reaction. It exhibits the composition-dependent activity with porous PtPb PNCs-40/ZnO being the most active for WGS to H_2, 16.9 times higher than that of the commercial Pt/C. The porous PtPb PNCs-40/ZnO also display outstanding durability with barely activity decay and negligible structure and composition changes after ten successive reaction cycles. X-ray photoelectron spectroscopy(XPS) results reveal that the suitable binding energy of Pt 4f_(7/2) and the high ratio of Pt(0)to Pt(II) in porous PtPb PNCs/ZnO and porous PtPb ONCs/ZnO are crucial for the enhanced WGS *** CO stripping results indicate the optimized CO adsorption strength on the Pt surface ensure the excellent WGS activity and the outstanding durability. The present work demonstrates an important advance in tuning the porous metal nanomaterials as highly efficient and durable catalysts for catalysis,energy conversion and beyond.

关键词： Porous Selective etching Hydrogen Pt-Pb Water-gas shift

The effects of exchange Rate Fluctuations on the Stock Price of Anglo-American PLC

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The Effects of Exchange Rate Fluctuations on the Stock Price...

作者： Baone v.Moshebashebi 上海师范大学

学位级别：硕士

Several variables influence the market prices of mining companies,such as inflation,exchange rates,interest rates,geopolitics,basic metal prices,*** purpose of this analysis is to examine the effect of such factors influencing the stock price of the Anglo-American mining company in South Africa and the United Kingdom,specifically,exchange,inflation,and interest rates with inflation and interest rates being controlled *** data from the Anglo-American Plc reports,the Johannesburg and London stock exchanges and the two countries’ central reserves are used as the statistics collection *** study uses a special case of panel data which is,time-series data and it adopts a longitudinal study or panel *** findings are evaluated using the application of R Statistical software through a linear data regression analysis *** data is tested for unit *** technical analysis used shows that exchange rates and stock prices significantly follow a random-walk *** variables are non-stationary at their level and they become stationary in their first *** tests and further statistical inferences are *** findings realized will shed some additional light on the risks involved in exchange rates and commodity prices for policymakers of countries dependent primarily on commodity *** findings show that there is a rather low statistically significant linear relationship between the USD/GBP exchange rate and the AAL: LO stock price in the short *** findings are reached for the USD/ZAR exchange rate and the ANG: JO stock *** means that there is no instantaneous effect of exchange rates on the stock price.

关键词： exchange Rate Stock Prices Cointegration ANOvA

Strong Suppression of Systemic Acquired Resistance in Arabidopsis by NRR is Dependent on its Ability to Interact with NPRland its Putative Repression Domain

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Molecular Plant 2008年第3期1卷 552-559页

作者： Mawsheng Chern Patrick e. Canlas Pamela C. Ronald Department of Plant Pathology University of California Davis CA 95616 USA

Systemic Acquired Resistance （SAR） in plants confers lasting broad-spectrum resistance to pathogens and requires the phytohormone salicylic acid （SA）. Arabidopsis NPR1/NIM1 is a key regulator of the SAR response. Studies attempting to reveal the function of NPR1 and how it mediates SA signaling have led to isolation of two classes of proteins that interact with NPRI＂ the first class includes rice NRR, Arabidopsis NIMIN1, NIMIN2, and NIMIN3, and tobacco NIMIN2-1ike proteins; the second class belongs to TGA transcription factors. We have previously shown that overexpression of N RR in rice suppresses both basal and Xa21-mediated resistance. In order to test whether NRR affects SA-induced, NPRl-mediated SAR, we have transformed Arabidopsis with the rice NRR gene and tested its effects on the defense response. expression of NRR in Arabidopsis results in suppression of PR gene induction by SAR inducer and resistance to pathogens. These phenotypes are even more severe than those of the nprl-1 mutant. The ability of NRR to suppress PR gene induction and disease resistance is correlated with its ability to bind to NPR1 because two point mutations in NRR, which reduce NPR1 binding, fail to suppress NPR1. In contrast, wild-type and a mutant NRR, which still binds to NPR1 strongly, retain the ability to suppress the SAR response. Replacing the C-terminal 79 amino acids of NRR with the vP16 activation domain turns the fusion protein into a transcriptional co-activator. These results indicate that NRR binds to NPR1 in vivo in a protein complex to inhibit transcriptional activation of PR genes and that NRR contains a transcription repression domain for active repression.

关键词： NRR NPR1 SA SAR disease resistance.

Plasma-Assisted Chemistry in High-Speed Flow

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Plasma Science and Technology 2007年第6期9卷 760-765页

作者： Sergey B.LeONOv Dmitry A.YARANTSev Anatoly P.NAPARTOvICH Igor v.KOCHeTOv Joint Institute for High Temperature Russian Academy of Science Izhorskaya str.13/19Moscow 125412Russia State

Fundamental problems related to the high-speed combustion are analyzed. The result of plasma-chemical modeling is presented as a motivation of experimental activity. Numerical simulations of the effect of uniform non-equilibrium discharge on the premixed hydrogen and ethylene-air mixture in supersonic flow demonstrate an advantage of such a technique over a heating. experimental results on multi-electrode non-uniform discharge maintenance behind wallstep and in cavity of supersonic flow are presented. The model test on hydrogen and ethylene ignition is demonstrated at direct fuel injection to low-temperature high-speed airflow.

关键词： high-speed combustion electrical discharge nonequilibrium kinetics

Atomic coordination dictates vibrational characteristics and thermal conductivity in amorphous carbon

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npj Computational Materials 2022年第1期8卷 525-531页

作者： Ashutosh Giri Connor J.Dionne Patrick e.Hopkins Department of Mechanical Industrial and Systems EngineeringUniversity of Rhode IslandKingstonRI02881USA Department of Mechanical and Aerospace engineering University of VirginiaCharlottesvilleVA22904USA Department of Materials Science and engineering University of VirginiaCharlottesvilleVA22904USA Department of Physics University of VirginiaCharlottesvilleVA22904USA

We discuss the role of atomic coordination in dictating the vibrational characteristics and thermal conductivity in amorphous *** systematic atomistic simulations on amorphous carbon structures at varying mass densities show the significant role played by the ratio of sp2 to sp3 hybridized bonds in dictating the contributions from propagating(phonon-like)and non-propagating vibrational modes and their influence on the overall thermal conductivities of the ***,our results show that as the concentration of sp3-bonded carbon atoms increases,the thermal conductivity can be increased by four fold,which is attributed to enhanced contributions from propagating modes in these amorphous *** results shed more light into the role of atomic coordination on dictating heat transfer mechanisms in amorphous materials,and also provide a deeper understanding of the ability to tune the thermal conductivity of amorphous carbon structures through the control of the local atomic coordination.

关键词： amorphous conductivity thermal

Osteoclast precursor differentiation by MCPIP via oxidative stress,endoplasmic reticulum stress,and autophagy

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分子细胞生物学报:英文版 2011年第6期3卷 360-368页

作者： Kangkai Wang Jianli Niu Hyunbae Kim Pappachan e.Kolattukudy Burnett School of Biomedical Sciences College of MedicineUniversity of Central FloridaOrlandoFL 32816USA

Osteoclasts(OCs)are responsible for bone resorption in inflammatory joint *** chemotactic protein-1(MCP-1)has been shown to induce differentiation of monocytes to OC precursors,but nothing is known about the underlying ***,we elucidate how MCPIP,induced by MCP-1,mediates this *** of MCPIP abolished MCP-1-mediated expression of OC markers,tartrate-resistant acid phosphatase,and serine protease cathepsin *** of MCPIP induced p47PHOX and its membrane translocation,reactive oxygen species formation,and induction of endoplasmic reticulum(eR)stress chaperones,up-regulation of autophagy marker,Beclin-1,and lipidation of LC3,and induction of OC *** of oxidative stress attenuated eR stress and autophagy,and suppressed expression of OC *** of eR stress by a specific inhibitor or by knockdown of IRe1 blocked autophagy and induction of OC *** stress inducers,tunicamycin and thapsigargin,induced expression of OC *** inhibition by 3′-methyladenine,LY294002,wortmannin or by knockdown of Beclin-1 or Atg 7 inhibited MCPIP-induced expression of OC *** results strongly suggest that MCP-1-induced differentiation of OC precursor cells is mediated via MCPIP-induced oxidative stress that causes eR stress leading to autophagy,revealing a novel mechanistic insight into the role of MCP-1 in OCs differentiation.

关键词： MCP-1 MCPIP osteoclast differentiation reactive oxygen species eR stress

exporting China’s Successes in vaccine Preventable Hepatitis

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China CDC weekly 2020年第30期2卷 575-576页

作者： Lance e.Rodewald National Immunization Program Chinese Center for Disease Control and PreventionBeijingChina

Almost four decades of science,innovation,and programmatic effort to control and prevent vaccinepreventable viral hepatitis have paid off spectacularly well in *** the pre-vaccine era,nearly 10% of children were infected by hepatitis B virus(HBv)—especially during childbirth—causing them to be lifelong carriers of HBv,able to infect others,and in great danger of liver cancer and cirrhosis as adults(1).

关键词： vaccine China. hepatitis

Forty and Twenty Years Ago and Now--virus elimination Successes and New Challenges

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China CDC weekly 2020年第50期2卷 953-954页

作者： Lance e.Rodewald National Immunization Program China CDC Immunization Services Division US CDC(2000-2012) WHO China Country Office(2012-2017)

Forty years ago,smallpox was declared eradicated by the World Health Organization(WHO).As ***,Director of the Smallpox eradication Programme at the WHO quoted from the 33^(rd) World Health Assembly(1980)(1),“...the world and all its peoples have won freedom from smallpox...a most devastating disease...since earliest time,leaving death,blindness,and disfigurement in its wake and which only a decade ago was rampant in Africa,Asia and South America.”

关键词： death Director disease.

Complete mitochondrial genomes of two deep-sea pandalid shrimps,Heterocarpus ensifer and Bitias brevis:insights into the phylogenetic position of Pandalidae(Decapoda:Caridea)

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Journal of Oceanology and Limnology 2020年第3期38卷 816-825页

作者： SUN Shao’e CHeNG Jiao SUN Song SHA Zhongli Department of Marine Organism Taxonomy and Phylogeny Institute of OceanologyChinese Academy of SciencesQingdao 266071China Deep Sea Research Center Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

The mitochondrial genome(mitogenome)analysis is a significant tool for investigating the evolutionary history of metazoan *** family Pandalidae is a diverse caridean group containing mainly deep-sea *** May 302019,only two complete mitogenomes are available in *** we present the complete mitogenome sequences of two deep-sea pandalid shrimps,Heterocarpus ensifer and Bitias brevis through Illumina *** mitochondrial genomes were determined to be 15939 bp and 15891 bp long,and both consist of 13 protein-coding genes(PCGs),23 transfer-RNA genes(tRNAs),two ribosomal-RNA genes(rRNAs),and one control *** nucleotide composition is biased toward adenine and ***,the gene contents and arrangements are consistent with the pancrustacean ground *** alignment of the control regions of four pandalids reveals a conserved sequence block(CSB)(104 bp in length,average GC%=29.47%and 69.23%similarity).A phylogenetic analysis based on 51 Caridea complete mitogenomes revealed that the deep-sea pandalid shrimps are situated an intermediate lineage,with a tendency to originated from those living in shallow sea area.

关键词： Pandalidae deep sea mitochondrial genome gene order phylogenetic relationships

e]iomimetic approaches toward smart bio-hybric systems

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Nano Research 2018年第6期11卷 3009-3030页

作者： Zhiqiang Luo Dara e. Weiss Qingyun Liu Bozhi Tian Colleae of Life Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Department of Chemistry The University of Chicago Chicago IL 606d7 USA The James Franck Institute The University of Chicago Chicago IL 60637 USA The Institute for Biophysical Dynamics The University of Chicago Chicago IL 60637 USA

Bio-integrated materials and devices can blur the interfaces between living and artificial systems. Microfluidics, bioelectronics, and engineered nanostructures, with close interactions with biology at the cellular or tissue levels, have already yielded a spectrum of new applications. Many new designs emerge, including of organ-on-a-chip systems, biodegradable implants, electroceutical devices, minimally invasive neuro-prosthetic tools, and soft robotics. In this review, we highlight a few recent advances of the fabrication and application of smart bio-hybrid systems, with a particular emphasis on the three-dimensional （3D） bio-integrated devices that mimic the 3D feature of tissue scaffolds. Moreover, neurons integrated with engineered nanostructures for wireless neuromodulation and dynamic neural output are briefly discussed. We also discuss the progress in the construction of cell-enabled soft robotics, where a tight coupling of the synthetic and biological parts is crucial for efficient function. Finally, we summarize the approaches for enhancing bio-integration with biomimetic micro- and nanostructures.

关键词： bio-integrated device bio-hybrid system biomimetics nano-bio interface