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Boosting CO_(2) hydrogenation to high-value olefins with highly stable performance over Ba and Na co-modified Fe catalyst

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Journal of Energy Chemistry 2023年第5期80卷 614-624,I0014页

作者： Joshua Iseoluwa Orege Na Liu Cederick Cyril Amoo jian Wei Qingjie Ge jian sun Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

CO_(2)hydrogenation has been considered to be a highly promising route for the production of high-value olefins(HVOs)while also mitigating CO_(2)***,it is challenging to achieve high selectivity and maintain stable performance for HVOs(ethylene,propylene,and linear a-olefins)over a prolonged reaction time due to the difficulty in precise control of carbon coupling and rapid catalyst ***,we present a selective Ba and Na co-modified Fe catalyst enriched with Fe_(5)C_(2)and Fe_(3)C active sites that can boost HVO synthesis with up to 66.1%selectivity at an average CO_(2)conversion of 38%for over 500 *** to traditional NaFe catalyst,the combined effect of Ba and Na additives in the NaBaFe-0.5 catalyst suppressed excess oxidation of FeCxsites by H_(2)*** absence of Fe3O4phase in the spent NaBaFe-0.5 catalyst reflects the stabilization effect of the co-modifiers on the *** study provides a strategy to design Fe-based catalysts that can be scaled up for the stable synthesis of HVOs from CO_(2)hydrogenation.

关键词： CO_(2)hydrogenation High-value olefins Barium additive Iron carbide Catalytic stability

Modeling TCP Incast Issue in Data Center Networks and an Adaptive Application-Layer Solution

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Journal of Electronic Science and Technology 2018年第1期16卷 84-91页

作者： Jin-Tang Luo Jie Xu jian sun School of Communication and Information Engineering University of Electronic Science and Technology of ChinaChengdu 611731

In data centers, the transmission control protocol(TCP) incast causes catastrophic goodput degradation to applications with a many-to-one traffic pattern. In this paper, we intend to tame incast at the receiver-side application. Towards this goal, we first develop an analytical model that formulates the incast probability as a function of connection variables and network environment settings. We combine the model with the optimization theory and derive some insights into minimizing the incast probability through tuning connection variables related to applications. Then,enlightened by the analytical results, we propose an adaptive application-layer solution to the TCP *** solution equally allocates advertised windows to concurrent connections, and dynamically adapts the number of concurrent connections to the varying conditions. Simulation results show that our solution consistently eludes incast and achieves high goodput in various scenarios including the ones with multiple bottleneck links and background TCP traffic.

关键词： Application-layer solution data center networks modeling transmission control protocol(TCP) incast

Physical Mechanism of the Impacts of the Tropical Atlantic Sea Surface Temperature on the Decadal Change of the Summer North Atlantic Oscillation

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Atmospheric and Oceanic Science Letters 2013年第5期6卷 365-368页

作者： sun jian-Qi Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Climate Change Research Center Chinese Academy of Sciences

In this study,physical mechanism of the impacts of the tropical Atlantic sea surface temperature(SST)on decadal change of the summer North Atlantic Oscillation(SNAO)was explored using an atmospheric general circulation model(AGCM)developed at the International Centre for Theoretical Physics(ICTP).The simulation results indicate that the decadal warming of the SST over the tropical Atlantic after the late 1970s could have significantly enhanced the convection over the *** enhanced convection would have strengthened the local meridional circulation over the Eastern Atlantic-North Africa-Western Europe region,exciting a meridional *** teleconnection might have brought the signal of the tropical Atlantic SST to the Extratropics,consequently activating the variability of the eastern part of the SNAO southern center,which led to an eastward shift of the SNAO southern center around the late *** physical processes are highly consistent with the previous observations.

关键词： summer North Atlantic Oscillation tropical Atlantic sea surface temperature teleconnection decadal change simulation

High temperature corrosion behavior of arc-sprayed aluminum coatings on steel

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 451-454页

作者： sun jian-bo WANG Yong DONG Li-xian College of Mechanical and Electronic Engineering University of Petroleum Dongying 257061 China College of Mechanical and Electronic Engineering University of Petroleum Dongying 257061 China College of Mechanical and Electronic Engineering University of Petroleum Dongying 257061 China

Aluminum coatings were sprayed on the substrate of steel Q235 by arc spraying. The test samples of Q235, Al coatings and Al coatings with seal coat were placed in box type electric resistance furnace at 400, 500,600, 650 ℃ when their oxidation behaviors were studied. And their oxidation kinetics curves were protracted. Microstructure, microhardness, bond strength and distribution of section elements were investigated by optical microscope(OM), Vickers microhardness instrument, electric tensile test machine and EPMA. Al coatings and Al coatings with seal coat can enhance the oxidation-resistance of substrate under 500 ℃. The latter has the best corrosion resistance. The coatings can't protect the substrate against oxidation above 600 ℃. After a long time corrosion there is enriched oxygen element at interface.

关键词： arc spraying Al coating Al coating with seal coat high temperature corrosion oxidation kineticscurve

Enthalpy of phase transition of isonicotinic acid

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Chinese Journal of Chemical Engineering 2017年第7期25卷 971-975页

作者： Dongfang Zhao Guanghui Liu jian sun Lisheng Wang School of Chemical Engineering and Environment Beijing Institute of TechnologyBelting 100081China

In this work, the group contribution method of Chickos et al. was applied to estimate the fusion enthalpy of isonicotinic acid, and the obtained result(29.2 k J·mol^(-1)) showed a large difference with the value(135 k J·mol^(-1)) as reported from literatures and as determined by differential scanning calorimetry(DSC). The results of DSC/TG measurement showed that the phase transition of isonicotinic acid from 187.27 °C to277.47 °C underwent a sublimation process, with a sublimation enthalpy of 128.03 k J·mol^(-1). An efficient analytical technique combining pyrolysis and gas chromatography/mass spectrometry(Py-GC/MS) was used to prove this conclusion.

关键词： lsonicotinic acid Enthalpy of fusion Group contribution method Enthalpy of sublimation Py-GC/MS

Ecosystem Health: Assessment Framework, Spatial Evolution, and Regional Optimization in Southwest China

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Chinese Geographical Science 2020年第1期30卷 142-156页

作者： ZHANG Hao sun jian DENG Wei PENG Li Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China School of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China College of Geography and Resources Sichuan Normal UniversityChengdu 610101China

Regional ecological health,the core of comprehensive ecosystem assessments,is an important foundation for regional exploration,environmental conservation,and sustainable *** mountainous areas in southwest China are backward in economy,but industrialization and urbanization have been rapid in recent *** study assessed the ecosystem health of the Sichuan and Yunnan provinces in China using a pressure-state-response(PSR)*** patterns of regional ecosystem health were analyzed from 2000 to 2016,including overall characteristics as well as local *** health in most regions was improved over time(Y=0.0058 X–11.0132,R2=0.95,P0.05).Overall,the regional ecosystems to the east of the Hu line-an imaginary line dividing east and west China into roughly equivalent parts-were healthier than those to the *** pressure and state scores of ecosystems were determined by physiographic condition,and the response scores by government policies and social *** spatiotemporal patterns of ecosystem health were dominated to a greater extent by natural than anthropogenic factors,which explains why the shift in the patterns aligned with the direction of the Hu *** regions into key management areas based on natural geographical conditions and socioeconomic development could contribute to the formulation of a reasonable ecological and environmental protection policy,guaranteeing ecosystem services in the long run.

关键词： ecosystem health spatiotemporal pattern pressure-state-response(PSR) standard deviational ellipse mountain area

Limited distribution and mechanism of the TetX4 tetracycline resistance enzyme

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Science Bulletin 2019年第20期64卷 1478-1481页

作者： Yongchang Xu Lizhang Liu jian sun Youjun Feng Department of Pathogen Biology&Microbiology and Department of General Intensive Care Unit of the Second Affiliated Hospital Zhejiang University School of MedicineHangzhou 310058China National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria South China Agricultural UniversityGuangzhou 510642China

Tetracyclines,a group of antimicrobial agents targeting protein synthesis,have been extensively used in agricultural,veterinary,and clinic settings[1].The sporadic rise in tetracycline resistance is partially due to the occurrence of efflux pumps and/or ribosome protection[1,2].The growing body of tetracycline-inactivating enzymes(e.g.,TetX(X1 to X4)[3,4]and Tet(47 to 55)[5])represents an alternative mechanism for tetracycline resistance,and threatens the renewed interest of tigecycline as a last-resort defense against lethal infections with carbapenem-resistant Enterobacteriaceae and Acinetobacter species.

关键词： Limited distribution and mechanism of the TetX4 tetracycline resistance enzyme

Preparation of Porous Polylactide Microspheres and Their Application in Tissue Engineering

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Chinese Journal of Polymer Science 2018年第6期36卷 712-719页

作者： Xu-Dong Shi Pei-jian sun Zhi-Hua Gan Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China The GAS Key Laboratory of Engineering Plastics Institute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China State Key Laboratory of Organic-inorganic Composites College of Life Science and TechnologyBeijing University of Chemical TechnologyBeijing 100029China

In this study, porous polylactide（PLA） microspheres with different structures were prepared through the multiple emulsion solvent evaporation method. By changing organic solvents（ethyl acetate and chloroform） and adding effervescent salt NH4 HCO3 in the inner water phase, microspheres with porous capsular, matrix, microcapsular and multivesicular structures were prepared. The protein encapsulation and release, and the cell growth behavior of porous microspheres were further explored. Under the same inner water phase, microspheres prepared with chloroform had higher protein encapsulation efficiency and less protein release rate as compared with those prepared with ethyl acetate. Cell experiments showed that the relatively rough surface of microspheres prepared with chloroform was more favorable for the cell growth in comparison with the smooth surface of microspheres prepared with ethyl acetate. This study shows a simple and effective method to control the protein release and cell growth behaviors of polymer microspheres by tuning their porous structure.

关键词： Polylactide Porous microspheres Drug release Cell Tissue engineering

Highly efficient charging and discharging of three-level quantum batteries through shortcuts to adiabaticity

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Frontiers of physics 2022年第3期17卷 101-109页

作者： Fu-Quan Dou Yuan-Jin Wang jian-An sun College of Physics and Electronic Engineering Northwest Normal UniversityLanzhou 730070China

Quantum batteries are energy storage devices that satisfy quantum mechanical *** to improve the battery’s performance such as stored energy and power is a crucial element in the quantum ***,we investigate the charging and discharging dynamics of a three-level counterdiabatic stimulated Raman adiabatic passage quantum battery via shortcuts to adiabaticity,which can compensate for undesired transitions to realize a fast adiabatic evolution through the application of an additional control field to an initial *** scheme can significantly speed up the charging and discharging processes of a three-level quantum battery and obtain more stored energy and higher power compared with the original stimulated Raman adiabatic *** explore the effect of both the amplitude and the delay time of driving fields on the performances of the quantum *** experimental implementation in superconducting circuit and nitrogen–vacancy center is also discussed.

关键词： quantum battery charging and discharging dynamics shortcuts to adiabaticity