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Photonics Research 2024年第9期12卷 1918-1926页

作者： bingxu chen JIE QIAO FEI HAN FU FENG SHIH-CHI chen Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong KongChina Zhejiang Lab Research Center for Humanoid SensingHangzhou 311100China

In two-dimensional(2D)material studies,tracking the anisotropic ultrafast carrier dynamics is essential for the development of optoelectronic ***,the anisotropic optical and electronic properties are investigated via either polarization-dependent Raman spectroscopy or field-effect transistors ***,study of the anisotropic transient carrier behaviors is still challenging,due largely to the lack of picosecond-resolved acquisition or programmable scanning capabilities in the current characterization *** this work,we select Ta_(2)NiSe_(5) as a model system to investigate the ultrafast anisotropic transportation properties of photo-excited carriers and transient polarized responses via a digital micromirror device(DMD)-based pumpprobe microscope,where the probe beam scans along the armchair and zigzag directions of a crystal structure via binary holography to obtain distinct carrier diffusion coefficients,*** results reveal the nonlinear diffusion behaviors of Ta_(2)NiSe_(5) in tens of picoseconds,which are attributed to the interplay between excited electrons and *** trend of the measured local polarization-dependent transient reflectivity is consistent with the polarized Raman spectra *** results show that the DMD-based pump-probe microscope is an effective and versatile tool to study the optoelectronic properties of 2D materials.

关键词： anisotropic mirror transient

Design of a 10 bit high resolution,high speed time-to-digital converter using a two-step pulse-train time amplifier

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The Journal of China Universities of Posts and Telecommunications 2018年第1期25卷 78-84页

作者： Wu Zebo chen bingxu Fan Chuanqi Wang Yuan Jia Song School of Electronic Engineering and Computer Science Peking University College of Communication and Information Technology Beijing University of Posts and Telecommunications

A high resolution and fast conversion rate time-to-digital converter （TDC） design based on time amplifier （TA） is proposed. The pulse-train TA employs a two-step scheme. The input time interval is first amplified by a N-times TA and the effective time is extracted in pulse-train using a time-register. Then the resulted interval is further amplified by the other pulse-train amplifier to obtain the final result. The two-step TA can thus achieve large gain that is critical for high resolution TDC. Simulation results in 1.2 V, 65 nm technology showed that for a 10 bit TDC, a resolution of 0. 8 ps and a conversion rate of 150 MS/s are achieved while consuming 2. 1 mW power consumption.

关键词： time-to-digital converter time amplifier two-step architecture time register

Active sites of Pt/CNTs nanocatalysts for aerobic base-free oxidation of glycerol

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Green Energy & Environment 2020年第1期5卷 76-82页

作者： Minjian Pan Jingnan Wang Wenzhao Fu bingxu chen Jiaqi Lei Wenyao chen Xuezhi Duan De chen Gang Qian Xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and Technology130 Meilong RoadShanghai200237China Department of Chemical Engineering Norwegian University of Science and TechnologyTrondheim7491Norway

Understanding the nature of Pt active sites is of great importance for the structure-sensitive base-free oxidation of glycerol. In the present work, the remarkable Pt particle size effects on glycerol conversion and products formation from the oxidation of the primary and the secondary hydroxyl groups are understood by combining the model calculations and DFT calculations, aiming to discriminate the corresponding dominant Pt active sites. The Pt(100) facet is demonstrated to be the dominant active sites for the glycerol conversion and the products formation from the two routes. The insights revealed here could shed new light on fundamental understanding of the Pt particle size effects and then guiding the design and optimization of Pt-catalyzed base-free oxidation of glycerol toward targeted products.

关键词： Base-free oxidation of glycerol Pt/CNTs catalyst Active sites Model calculations DFT calculations

Mechanistic aspects of facet-dependent CH_(4)/C_(2+)selectivity over aχ-Fe_(5)C_(2)Fischer-Tropsch catalyst

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Green Energy & Environment 2022年第3期7卷 449-456页

作者： Thanh Hai Pham Junbo Cao Nan Song Yueqiang Cao bingxu chen Gang Qian Xinggui Zhou De chen Xuezhi Duan State Key Laboratory of Chemical Engineering East China University of Science and Technology130 Meilong RoadShanghai200237China Vietnam Institute for Tropical Technology and Environmental Protection 57A Truong Quoc DungHo Chi MinhViet Nam Department of Chemical Engineering Norwegian University of Science and TechnologyN-7491TrondheimNorway

Structure-performance relationship is a complex issue in iron-catalyzed Fischer-Tropsch synthesis,and it is not easy to elucidate it by experimental ***-principle calculation is a powerful method for explaining experimental results and guiding catalyst *** this study,we investigated the reaction mechanisms of CH_(4)formation and C-C coupling on fourχ-Fe_(5)C_(2)surfaces and established the kinetic equations to compare the rates of CH_(4)formation and C_(1)+C_(1)coupling reactions and determine the CH_(4)/C_(2+)*** results show that the geometry of theχ-Fe_(5)C_(2)surfaces has little effect on the formation rate of CH_(4);however,the C_(1)+C_(1)coupling reactions are significantly affected by the surface *** C_(1)+C_(1)coupling reaction rates on the terraced-like(510)and(021)surfaces are much higher than those on the stepped-like(001)and(100)*** on these results,we established a Brùnsted-Evans-Polanyi(BEP)relationship between the effective barrier difference for CH_(4)formation and C_(1)+C_(1)coupling(ΔE_(eff))and the adsorption energy of C+4H(ΔE_(C+4H))onχ-Fe_(5)C_(2)surfaces.ΔE_(C+4H)can be used as a descriptor for CH_(4)/C_(2+)selectivity on different surfaces ofχ-Fe_(5)C_(2).

关键词： selectivity catalyst coupling

Taming Electrons in Pt/C Catalysts to Boost the Mesokinetics of Hydrogen Production

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Engineering 2022年第7期8卷 124-133页

作者： Wenyao chen Wenzhao Fu Xuezhi Duan bingxu chen Gang Qian Rui Si Xinggui Zhou Weikang Yuan De chen State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201204China Department of Chemical Engineering Norwegian University of Science and TechnologyTrondheim N-7491Norway

Taming the electron transfer across metal–support interfaces appears to be an attractive yet challenging methodology to boost catalytic ***,we demonstrate a precise engineering strategy for the carbon surface chemistry of Pt/C catalysts—that is,for the electron-withdrawing/donating oxygencontaining groups on the carbon surface—to fine-tune the electrons of the supported metal *** the ammonia borane hydrolysis as an example,a combination of density functional theory(DFT)calculations,advanced characterizations,and kinetics and isotopic analyses reveals quantifiable relationships among the carbon surface chemistry,Pt charge state and binding energy,activation entropy/enthalpy,and resultant catalytic *** decoupling the influences of other factors,the Pt charge is unprecedentedly identified as an experimentally measurable descriptor of the Pt active site,contributing to a 15-fold increment in the hydrogen generation *** incorporating the Pt charge with the number of Pt active sites,a mesokinetics model is proposed for the first time that can individually quantify the contributions of the electronic and geometric properties to precisely predict the catalytic *** results demonstrate a potentially groundbreaking methodology to design and manipulate metal–carbon catalysts with desirable properties.

关键词： Mesokinetics model Catalyst descriptor Pt charge state Carbon surface chemistry Hydrogen generation activity

Multi-omics analysis reveals the molecular regulatory network underlying the prevention of Lactiplantibacillus plantarum against LPS-induced salpingitis in laying hens

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Journal of Animal Science and Biotechnology 2024年第1期15卷 427-441页

作者： Dan Song Aike Li bingxu chen Jia Feng Tao Duan Junlin cheng Lixian chen Weiwei Wang Yuna Min College of Animal Science and Technology Northwest A&F UniversityShaanxiPeople’s Republic of China Key Laboratory of Grain and Oil Biotechnology of National Food and Strategic Reserves Administration Academy of National Food and Strategic Reserves AdministrationBeijingPeople’s Republic of China

Background Salpingitis is one of the common diseases in laying hen production, which greatly decreases the economic outcome of laying hen farming. Lactiplantibacillus plantarum was effective in preventing local or systemic inflammation, however rare studies were reported on its prevention against salpingitis. This study aimed to investigate the preventive molecular regulatory network of microencapsulated Lactiplantibacillus plantarum(MLP) against salpingitis through multi-omics analysis, including microbiome, transcriptome and metabolome *** The results revealed that supplementation of MLP in diet significantly alleviated the inflammation and atrophy of uterus caused by lipopolysaccharide(LPS) in hens(P < 0.05). The concentrations of plasma IL-2 and IL-10 in hens of MLP-LPS group were higher than those in hens of LPS-stimulation group(CN-LPS group)(P < 0.05). The expression levels of TLR2, MYD88, NF-κB, COX2, and TNF-α were significantly decreased in the hens fed diet supplemented with MLP and suffered with LPS stimulation(MLP-LPS group) compared with those in the hens of CN-LPS group(P < 0.05). Differentially expressed genes(DEGs) induced by MLP were involved in inflammation, reproduction, and calcium ion transport. At the genus level, the MLP supplementation significantly increased the abundance of Phascolarctobacterium, whereas decreased the abundance of Candidatus_Saccharimonas in LPS challenged hens(P < 0.05). The metabolites altered by dietary supplementation with MLP were mainly involved in galactose, uronic acid, histidine, pyruvate and primary bile acid metabolism. Dietary supplementation with MLP inversely regulates LPSinduced differential metabolites such as Lyso PA(24:0/0:0)(P < 0.05).Conclusions In summary, dietary supplementation with microencapsulated Lactiplantibacillus plantarum prevented salpingitis by modulating the abundances of Candidatus_Saccharimonas, Phascolarctobacterium, Ruminococcus_torques_group and Eubacterium_hallii_group w

关键词： Laying hen Metabolome Microbiome Microencapsulated Lactiplantibacillus plantarum Salpingitis Transcriptome

Iron-based Fischer–Tropsch synthesis of lower olefins: The nature of χ-Fe_5C_2 catalyst and why and how to introduce promoters

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Journal of Energy Chemistry 2016年第6期25卷 911-916页

作者： Di Wang bingxu chen Xuezhi Duan De chen Xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and Technology Department of Chemical Engineering Norwegian University of Science and Technology

As a sustainable and short-flow process, iron-catalyzed direct conversion of CO-rich syngas to lower olefins without intermediate steps, i.e., Fischer–Tropsch-to-Olefins (FTO), has received increasing attention. However, its fundamental understanding is usually limited by the complex crystal phase composition in addition to the interferences of the promoter effects and inevitable catalyst deactivation. Until recently, the combination of multiple in-situ/ex-situ characterizations and theoretical studies has evidenced Hägg iron carbide (χ-Fe5C2) as the dominant active phase of iron-based Fischer–Tropsch catalysts. This perspective attempts to review and discuss some recent progresses on the nature of χ-Fe5C2catalyst and the crucial effects of promoters on the FTO performance from theoretical and experimental viewpoints, aiming to provide new insights into the rational design of iron-based FTO catalysts. © 2016 Science Press

关键词： Carbides Catalyst deactivation Catalysts Iron Olefins Phase composition

Analysis on Characters and Application Potential of a Sorghum Sterile Line ‘Ji2055A’

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Agricultural Biotechnology 2012年第5期1卷 14-17页

作者： Jihong LI bingxu chen Shijie GAO Institute of Crop Resources Jilin Academy of Agricultural Sciences

＇ Ji2055A＇ is a superior sterile line sorghum bred by Institute of Crop Resources, Jilin Academy of Agricultural Sciences. It has a growing season of 112 days and a plant height of 70 cm. With a stable sterility rate of 100%, ＇ Ji2055A＇ has a stable male sterility and highly viable stignms. Selfing won＇t lead to seeds, This sterile line is strongly resistant to drought and lodging in addition to resistance to leaf spot and head smut. Generally, it has a yield of 3 000 -4 000 kg/hm2 and the hybrid seed yield is between 4 000 - 5 000 kg/hm2, with a high combining ability. There are six varieties approved by the state and the province, as well as another eight new combines under regional testing. The obtained hybrids are strongly resistant, widely adaptable with a great potential to increase yield, ＇ Ji2055A＇ has promoted the breeding and production of spring early maturing sorghum in China.

关键词： Sorghum Sterile line ' Ji2055A' Characters Application

求解电路仿真中超大规模稀疏线性方程组的改进分块对角加边方法

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计算数学 2024年第4期46卷 529-546页

作者：陈炳旭寇彩霞陈圣杰数学与信息网络教育部重点实验室(北京邮电大学) 北京100876 北京邮电大学理学院北京100876 中国科学院数学与系统科学研究院北京100190 中国科学院大学数学科学学院北京100049

针对电路仿真中瞬态分析产生的超大规模稀疏线性方程组,分块对角加边(Bordered Block Diagonal,BBD)方法是一类经典的求解方法.本文提出了一种改进的BBD方法,通过使用基础列分解和流水线分解结合的方式,改善了传统BBD方法中负载不均衡... 详细信息

针对电路仿真中瞬态分析产生的超大规模稀疏线性方程组,分块对角加边(Bordered Block Diagonal,BBD)方法是一类经典的求解方法.本文提出了一种改进的BBD方法,通过使用基础列分解和流水线分解结合的方式,改善了传统BBD方法中负载不均衡的问题.在矩阵边界分解时,本文通过引入流水线分解克服了传统方法边界难以并行的缺陷.通过求解16个真实电路上产生的超大规模稀疏线性方程组,我们验证了改进BBD方法的有效性.相较于传统的BBD方法,改进方法在不同线程下的求解速度均有一定提升.

关键词：分块对角加边方法超大规模稀疏线性方程组电路方程组稀疏LU分解电路仿真并行计算

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大视场大相对孔径自由曲面成像系统设计

红外与激光工程 2020年第8期49卷 257-265页

作者：陈炳旭廖志远操超白瑜牟达长春理工大学光电工程学院吉林长春130022 中国科学院光电技术研究所四川成都610209

近年来,自由曲面在高性能离轴反射成像系统中应用越来越广泛。文中基于矢量像差理论和遗传算法求解初始结构,采用视场离轴和孔径离轴相结合的方式,利用XY多项式描述的自由曲面增大自由度校正离轴像差,设计了一个大视场大相对孔径的制冷... 详细信息

近年来,自由曲面在高性能离轴反射成像系统中应用越来越广泛。文中基于矢量像差理论和遗传算法求解初始结构,采用视场离轴和孔径离轴相结合的方式,利用XY多项式描述的自由曲面增大自由度校正离轴像差,设计了一个大视场大相对孔径的制冷型离轴反射光学系统。系统工作波段为长波红外8~12μm,焦距400 mm,F数为2,视场角为8°×5°,平均RMS波像差为0.037054λ(λ=9μm)。探测器冷光阑和光学系统出瞳相匹配,实现100%冷光阑效率,系统能量集中度较高,成像质量良好。

关键词：自由曲面成像系统大视场大相对孔径冷光阑匹配