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Middle Jurassic climate oscillations from paleosol records of the Sichuan Basin,SW China

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Journal of Palaeogeography 2022年第1期11卷 97-122页

作者： Jun Li cheng-Min Huang Guo-Lin Yang yuan-yuan Pan Xing-yue Wen College of Urban Environment Lanzhou City UniversityLanzhou 730070Gansu ProvinceChina Department of Environmental Science and Engineering Sichuan UniversityChengdu 610065Sichuan ProvinceChina BaiLie School of Petroleum Engineering Lanzhou City UniversityLanzhou 730070Gansu ProvinceChina School of Environmental Science and Engineering China West Normal UniversityNanchong 637002Sichuan ProvinceChina

The Middle Jurassic is characterized by major plate tectonic changes,variable atmospheric CO_(2)concentrations(pCO_(2)),and climate oscillations in both marine and terrestrial ***,the limited evidence from the terrestrial sedimentary records hampers a comprehensive understanding of global climate state in this ***-exposed strata of the Shaximiao Formation in the Sichuan Basin,Southwest China,preserve successions of paleosols that offer the possibility of evaluating the terrestrial paleoclimatic changes during the Middle Jurassic(Bajocian to Callovian).A total of 151 paleosol profiles belonging to four paleosol types(Entisol-like,Inceptisol-like,Aridisol-like and argillic Inceptisol-like paleosols)were identified and *** quantitative paleoclimate reconstructions based on the bulk geochemistry of paleosol horizons and depths of carbonate nodules indicate a generally semiarid-subhumid climate alternating with arid-humid and cool/warm-temperate climates during this time *** dynamic climate terminated in a dry,subhumid,humid/perhumid and superhumid moisture regime characterized by steppe/wet or rain forest floral *** suggest that these climatic fluctuations may have been related to global geodynamic(e.g.,the fragmentation of Pangea,“megamonsoonal”circulation,and bolide impacts)and regional tectonic uplift(e.g.,the uplift of the Longmenshan Mountains in the South China Block)during the Middle *** pCO_(2)estimates suggest relatively low pCO_(2)levels within the range of~100 ppm-~890 ppm during the Bajocian to *** results coincide with the threshold for the initiation of glaciation and may help to explain the occurrence of cool intervals in the generally warm *** pCO_(2)fluctuations,which coincide with paleotemperature variations in the low paleolatitudes of the Northern Hemisphere,are possibly attributable to global geological events(e.g.,wildfire events,eustatic sea-level oscillations,and th

关键词： Paleosols Paleoprecipitation Paleotemperature Paleoatmospheric CO_(2) Shaximiao Formation Bajocian-Callovian

A new fluorescent probe with ultralow background fluorescence for imaging of endogenous cellular selenol under oxidative stress

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Chinese Chemical Letters 2017年第10期28卷 1987-1990页

作者： Dan cheng yue Pan Bin-cheng Yin Lin yuan Xiao-Bing Zhang State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China Lab of Biosystem and Microanaiysis State Key Laboratory of Bioreactor Engineering East China University of Sdence and Technology Shanghai 200237 China

A new fluorescent probe（Rhod-Sec） for selenol detection with ultralow background fluorescence have been developed in this paper, which showed a 380-fold off-on fluorescence response, and the nontoxic Rhod-Sec is well suitable for detecting and imaging both exogenous and endogenous selenol in living cells. It also can be applied to visualize the fluctuation of selenol in HepG2 cells through LPS-induced cells oxidation resistance.

关键词： Fluorescent probe Selenol Fluorescent imaging Oxidative stress

Corrosion behaviour of NiCrFeAl-hBN seal coatings in oxidation environments at a high temperature

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Rare Metals 2021年第1期40卷 212-218页

作者： Su-yuan Yang Dan Guo Xing-Wang cheng Jian-Ming Liu yue-Guang Yu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081.China National Key Laboratory of Science and Technol Beijing General Research

The purpose of this investigation was to evaluate the microstructure,high-temperature oxidation behaviour,and hardness of a seal coating under controlled exposures at 750℃with different exposure *** results reveal that the main phases in the coating are Ni,FeNi3,and hexagonal BN,withα-Al_(2)O_(3)peaks appearing after 2-h *** the exposure time increases,the diffraction peak intensity ofα-Al_(2)O_(3)begins to decrease and Cr_(2)O_(3)peaks appear after 200 *** 1000 h,Cr_(2)O_(3)becomes dominant with only small amounts ofα-Al_(2)O_(3)*** high-temperature oxidation process of the coating includes three stages:the fast stage,transition stage,and slow *** oxidation rate is constant in each stage,and in the fast stage and slow stages with values of7.9×10^(-4)and 8.37×10^(-5)mg^(2)·cm^(-4)·s^(-1),***,α-Al_(2)O_(3)forms near the pores in the coating,followed by the formation of Cr_(2)O_(3).As the exposure time increases,oxidation penetrates into the interior of the coating along phase boundaries to form island-shaped inner oxide layers with high concentrations of Cr,Ni,and ***,hardness increases with increasing oxide percentage.

关键词： NiCrFeAl-hBN Seal coating Oxidation Microstructure High temperature

Effects of Mo addition on microstructure of a 4th generation Ni-based single crystal superalloy

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Progress in Natural Science:Materials International 2022年第6期32卷 745-751页

作者： yuan cheng Xinbao Zhao Wanshun Xia Qinghai Pan Quanzhao yue yuefeng Gu Ze Zhang Institute of Superalloys Science and Technology School of Materials Science and Engineering Zhejiang University

The effects of Mo addition on the microstructure of a 4th generation Ni-based single crystal superalloy were *** addition significantly promoted elements Mo,W and Re partition into γ phase and enhanced absolute lattice misfit at 1100℃.The increase of Mo concentration from 2 wt% to 4 wt% also decreased the content of eutectic islands and the segregation ratios of other alloying elements in the as-cast state,especially Re and *** heat treatments,the size of γ' phase and width of γ channels decreased slightly with higher Mo *** Mo additions slightly enhanced the segregation behavior of Re while reducing the segregation behavior of ***,it revealed that the primary and secondary dendrite arm spacings were barely affected by Mo addition.

关键词： Ni-based single crystal superalloys Mo Segregation ratio Lattice misfit

Demonstration of 60 GHz millimeter-wave short-range wireless communication system at 3.5 Gbps over 5 m range

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Science China(Information Sciences) 2017年第8期60卷 70-76页

作者： Guangrong yue Zhiqiang WANG Lei CHEN Long cheng Junlin TANG Xianbing ZOU yuan ZENG Lianming LI National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory 54th Research Institute of China Electronics Technology Group Corporation Shanghai Institute of Aerospace System Engineering School of Information Science and Engineering Southeast University

Millimeter-wave communication has received considerable attention for use in new-generation broadband wireless communication because of the scarcity of microwave band spectrum resources. The unlicensed frequency band at 60 GHz is suitable for indoor short-range broadband communication. In this paper, we introduce a 60 GHz millimeter-wave short-range wireless communication demo system adhering to the IEEE 802.11 ad standard and targeting high-definition video streaming transmission. The system uses single-carrier transmission with frequency-domain equalization. The hardware prototype consists of a 65-nm CMOS radio-frequency front-end and a baseband transceiver for the physical layer functions. Important baseband technologies such as carrier synchronization, phase noise compensation, frequency-domain equalization, and low-density parity-check decoding based on probability calculation are also discussed. The system performance is demonstrated in an experiment on high-definition video transmission, where a data rate of 3.52 Gbps is achieved with a quadrature phase-shift keying signal over a distance of 5.109 m.

关键词： 60 GHz millimeter-wave IEEE 802 11ad SC-FDE 65-nm CMOS

Lanthanide-containing persistent luminescence materials with superbright red afterglow and excellent solution processability

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Science China Chemistry 2021年第12期64卷 2125-2133页

作者： Ming Xu Jia Liu Xianlong Su Qianwen Zhou Hang yuan yue Wen Yihang cheng Fuyou Li Department of Chemistry&State Key Laboratory of Molecular Engineering of Polymers Fudan UniversityShanghai200433China Shanghai Taywell Biotechnology Co. Ltd.Shanghai200438China

Lanthanide-containing persistent luminescence materials are promising candidates for a wide range of applications by virtue of splendid superiorities in afterglow ***,it is a crucial challenge to achieve high-quality afterglow materials at the attractive nanoscale,with uniform size,controllable morphology,and satisfying ***,a bottom-up approach was developed to construct the high-quality afterglow nanoparticles,incorporating luminescent lanthanide complex and organic molecular ingredients under mild *** nanoparticles exhibited intrinsic lanthanide luminescence with superbright red afterglow(>10 cd m^(−2))in a homogeneous *** afterglow solution with excellent processability can serve as ideal building blocks for the on-demand fabrication of functional ***-dispersible afterglow nanoparticles with state-of-the-art high brightness were uniformly constructed to perform whole-blood lateral flow assay of procalcitonin with a naked-eye detection limit of 0.5 ng mL^(−1),promoting the point-of-care testing development.

关键词： persistent luminescence lanthanide photochemical afterglow solution processing point-of-care testing

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Diesel molecular composition and blending modeling based on SUBEM framework

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Petroleum Science 2022年第2期19卷 839-847页

作者： yue-Ming Guan Dong Guan cheng Zhang Sheng-Hua yuan Guang-Qing Cai Lin-Zhou Zhang State Key Laboratory of Heavy Oil Processing Petroleum Molecular Engineering Center(PMEC)China University of PetroleumBeijing102249China SINOPEC Dalian Research Institute of Petroleum and Petrochemicals SINOPECDalian116045LiaoningChina

Diesel molecular compositional model has important application for diesel quality prediction,blending,and molecular-level process model *** this paper,different types of diesel molecular compositional and blending models were constructed based on the SU-BEM *** than 1500 representative molecules were selected to form the molecular structure *** probability density functions(PDFs)combination was determined by experimental data and experience.A quadratic optimization strategy combining genetic algorithm with local optimization algorithm was adopted to improve the accuracy of the compositional *** model results show good agreement with the experimental *** diesel blending model was constructed at the molecular-level based on the above diesel compositional *** properties of the blending model accord with the experimental *** is proved that the compositional models and blending model constructed have high accuracy and strong prediction capability,and are applicable to the industrial process.

关键词： Molecular compositional model Molecular blending model SU-BEM Framework Diesel

Electrochemical Performance and Capacity Fading Mechanism of LiFePO4 at Different pH Aqueous Electrolyte Solutions

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Chinese Journal of Chemical Physics 2015年第3期28卷 315-322,I0002页

作者： yuan Yin yue-hua Wen Yong-lai Lu Jie cheng Gao-ping Cao Yu-sheng Yang College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China Research Institute of Chemical Defence Beijing 100191 China

The electrochemical stability of LiFePO4 in a Li＋-containing aqueous electrolyte solution is critically dependent on the pH value of the aqueous solution. It shows a considerable decay in capacity of LiFePO4 upon cycling when the pH value is increased to 11. The mechanism responsible for the capacity fading is extensively investigated by means of cyclic voltammogram, ac impedance, charge/discharge, ex situ X-ray diffraction, and chemical analysis. LiFePO4 is relatively electrochemically stable in LiNO3 aqueous solution with pH=7. But the electrochemical performance of LiFePO4 in aqueous electrolyte is inferior to that in organic electrolyte. It is attributed to the loss of Li and the Fe, P dissolution during prolonged charge-discharge in aqueous medium. A precipitate is formed on the surface of LiFePO4 electrodes. It results in the change of crystalline structure, a large electrode polarization, and capacity fading.

关键词： Olivine LiFePOa Aqueous electrolyte Electrochemical property Capacityfade Mechanism

Facile synthesis of sulfurized polyacrylonitrile composite as cathode for high-rate lithium-sulfur batteries

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Journal of Energy Chemistry 2020年第10期29卷 161-165页

作者： Jingwei Xiang Zezhou Guo Ziqi Yi Yi Zhang Lixia yuan Zexiao cheng yue Shen Yunhui Huang State Key Laboratory of Material Processing and Die&Mold Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

Sulfurized polyacrylonitrile(SPAN)as a promising cathode material for lithium sulfur(Li-S)batteries has drawn increasing attention for its improved electrochemical performance in carbonate-based ***,the relatively poor electronic and ionic conductivities of SPAN limit its high-rate and lowtemperature *** this work,a novel one-dimensional nanofiber SPAN(SFPAN)composite is developed as the cathode material for Li-S *** from its one-dimensional nanostructure,the SFPAN composite cathode provides fast channels for the migration of ions and electronics,thus effectively improving its electrochemical performance at high rates and low *** a result,the SFPAN maintains a high reversible specific capacity^1200 mAh g−1 after 400 cycles at 0.3 A g−1 and can deliver a high capacity of^850 mAh g−1 even at a high current density of 12.5 A g−*** is more,the SFPAN can achieve a capacity of^800 mAh g−1 at 0℃and^1550 mAh g−1 at 60℃,thus providing a wider temperature range of *** work provides new perspectives on the cathode design for high-rate lithium-sulfur batteries.

关键词： Sulfurized polyacrylonitrile One-dimensional nanofiber High-rate peformance Lithium sulfur batteries