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Science China(Physics,Mechanics & Astronomy) 2020年第4期63卷 73-87页

作者： hai-Shan Liu Zhan-Feng Mai Yue-Zhou Li h.lu Center for Joint Quantum Studies and Department of Physics Tianjin UniversityTianjin 300350China Institute for Advanced Physics&Mathematics Zhejiang University of TechnologyHangzhou 310023China

We introduce the quasi-topological electromagnetism which is defined to be the squared norm of the topological 4-form F ∧ F. A salient property is that its energy-momentum tensor is of the isotropic perfect fluid with the pressure being precisely the opposite to its energy density. It can thus provide a model for dark energy. We study its application in both black hole physics and *** quasi-topological term has no effect on the purely electric or magnetic Reissner-Nordstr o¨m black holes, the dyonic solution is however completely modified. We find that the dyonic black holes can have four real horizons. For suitable parameters, the black hole can admit as many as three photon spheres, with one being stable. Another intriguing property is that although the quasitopological term breaks the electromagnetic duality, the symmetry emerges in the on-shell action in the Wheeler-De Witt patch. In cosmology, we demonstrate that the quasi-topological term alone is equivalent to a cosmological constant, but the model provides a mechanism for the dark energy to couple with other types of matter. We present a concrete example of the quasi-topological electromagnetism coupled to a scalar field that admits the standard FLRW cosmological solutions.

关键词： quasi-topological electromagnetism dark energy black holes photon spheres electromagnetic duality

A COMPARATIVE STUDY OF QUADRATURE SAMPLING AND DIRECT SAMPLING OF BANDPASS SIGNALS

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A COMPARATIVE STUDY OF QUADRATURE SAMPLING AND DIRECT SAMPLI...

International Conference on Signal Processing(ICSP’90)

作者： Chung h.lu Danmei Chang Ray Chapel Department of Electrical Engineering Center for Communications and Signal Processing Research New Jersey Institute of Technology University heights NewarkNew Jersey 07102USA

＜正＞Various techniques have been studied for the sampling of bandpass *** this paper,we present a comparative study of quadrature sampling and direct sampling of bandpass ***,both schemes provide efficient sampling of a bandpass signal at a minimum data rate and at the same time demultiplex the in-phase and quadrature components. In reality,imperfect circuit parameters lead to nonideal sampling, resulting in quadrature *** form relations for quadrature interference for quadrature sampling and direct sampling are derived and *** analysis shows that quadrature interference is inversely proportional to the variance of sampling phase jittering.

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A Program for Determining Impeller Geometric Parameters with Minimum Shaft Power

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A Program for Determining Impeller Geometric Parameters with...

第十七届全国水动力学研讨会暨第六届全国水动力学学术会议

作者： J. Yan h. lu (Sichuan Institute of Technology,Chengdu, Sichuan, China) h.lu (South Dakota State University, Brookings, SD, USA)

＜正＞Because of increasing energy-saving awareness, the main target involved in centrifugal impeller design practice was focused on improving pump efficiency in the past. All impeller geometric parameters were determined in the requirements of reducing all types of losses in the impeller. In many applications. however, reliability of the pump must be highlighted and reducing the maximum power absorbed by the pump becomes the most important objective of the design. A novel program for determining geometric parameters of centrifugal impellers is presented in this paper, in which objective and procedure associated with impeller geometry calculation are completely different from those of traditional methods. This approach offers a new means for impeller designers in dealing with pumps with specially required performance characteristics.

关键词： Centrifugal pump impeller parameter optimization

圆孔边缘裂纹扩展过程中裂纹周围的动态塑性应变测量

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实验力学 1986年第4期 345-352页

作者： F.P.Ching 董本涵 h.lu W.Robert 美国纽约州立大学石溪分校机械系实验力学研究室沈阳六○六所美国纽约州立大学石溪分校机械系实验力学研究室美国纽约州立大学石溪分校机械系实验力学研究室教授研究生研究生

本文用面内云纹法和影象云纹法结合高速摄影技术,对带孔铝板在突加载荷作用下孔边裂纹扩展过程中裂纹周围的应变场进行分析。用等应变线表达断裂过程中相应时刻的应变场,最大动应变可达0.9。本试验也得到了材料的裂纹扩展速度和撕裂模量。

关键词：面内云纹法影象云纹法高速摄影技术圆孔边缘裂纹扩展过程动态塑性应变扩展速度撕裂模量

Molecular Dynamics Simulations of Sticking and Diffusion of Atomic Carbon on Tungsten Surfaces

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Molecular Dynamics Simulations of Sticking and Diffusion of ...

9th International Conference on Computer Simulation of Radiation Effects in Solids

作者： Zhongshi Yang~(1 *) Q.Xu~1 G.-h.lu~2 G.-N.luo~1 1 Institute of Plasma Physics Chinese Academy of Sciences hefei 230031 China 2 Department of Physics Beijing University of Aeronautics andAstronautics Beijing 100083 China

＜正＞Tungsten and its alloys have been considered as candidate plasma-facing materials （PFMs） for ITER,future DEMO reactors and EAST[1].As long as both elements, tungsten and carbon,are introduced in the main chamb... 详细信息

关键词： molecular dynamics simulations carbon tungsten sticking diffusion

Weak Acid-Base Interaction Induced Assembly for the Synthesis of hollow Carbon Nanospheres

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Weak Acid-Base Interaction Induced Assembly for the Synthesi...

中国化学会第28届学术年会

作者： Qiang Sun,G.-h.Wang,R.Zhang,W.-C.Li,X.-Q.Zhang,A.-h.lu State Key Laboratory of Fine Chemicals,School of Chemical Engineering,Faculty of Chemical,Environmental and Biological Science and Technology,Dalian University of Technology,Dalian 116024,P.R.China

＜正＞Synthesis of hollow carbon nanospheres（hCS）have been the focus of intensive research,because of their large fraction of void space in hollow structures,excellent chemical stability,and potential applications i... 详细信息

关键词： hollow Carbon Nanospheres hydrothermal Synthesis Weak Acid-Base Interaction.

Rational design of AgGaS/ZnS/ZnS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

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Journal of Materials Science & Technology 2024年第2期169卷 235-242页

作者： h.X.lu h.Liu Z.Z.Fu Y.Y.Chen h.Q.Dai Z.hu W.L.Zhang R.Q.Guo Institute for Electric Light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future Lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu Research Institute of Fudan University YiwuZhejiang 322000China Zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/ZnS/ZnS quantum dots(QDs).In the first step,an inner ZnS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer ZnS shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesized AgGaS/ZnS/ZnS QDs showed an excellent photoluminescence quantum yield(PLQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PLQY reported thus far for AgGaS ***,the effect of halogen ions in Zn precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between Zn cation diffusion and ZnS shelling ***,the ZnS shelling reaction was dominant when ZnCl_(2)was employed,while Zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the ZnS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell Alloyed core/shell interface

卵巢癌中肿瘤抑制性印迹基因PEG3的遗传及表遗传调节

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卵巢癌中肿瘤抑制性印迹基因PEG3的遗传及表遗传调节

中华医学会第九次全国妇科肿瘤学术会议

作者：冯炜炜 Rebecca T．Marquez 吕真刘劲松 Karen h.lu 郁茵华 Robert C．Bast Jr 复旦大学附属妇产科医院 Department of Experimental Therapeutics The University of Texas M．D．Anderson CancerHoustonTexas770030

目的:研究卵巢癌中印迹基因PEG4遗传及表遗传调节。方法:我们用cDNA微阵列法筛选在卵巢癌中降表达的印迹基因,并进一步采用基因转染及克隆形成试验研究PEG3的肿瘤抑制作用;用实时逆转录PCR、Pyrosequencing定量检测PEG3在10个卵巢癌细...

目的:研究卵巢癌中印迹基因PEG4遗传及表遗传调节。方法:我们用cDNA微阵列法筛选在卵巢癌中降表达的印迹基因,并进一步采用基因转染及克隆形成试验研究PEG3的肿瘤抑制作用;用实时逆转录PCR、Pyrosequencing定量检测PEG3在10个卵巢癌细胞株、42对卵巢癌组织及邻近正常组织中的表达、甲基化修饰及等位基因杂和性缺失(LOh)。5个正常卵巢上皮细胞株及5个正常人卵巢上皮作为

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Renewable biosynthesis of isoprene from wastewater through a synthetic biology approach:the role of individual organic compounds

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 13-24页

作者： Min Yang Xianghui Li Weixiang Chao Xiang Gao huan Wang lu lu State Key Laboratory of Urban Water Resource and Environment School of Civil and Environmental EngineeringHarbin Institute of TechnologyShenzhen 518055China Center for Materials Synthetic Biology CAS Key Laboratory of Quantitative Engineering Biology of CASShenzhen Institute of Synthetic BiologyShenzhen Institutes of Advanced TechnologyChinese Academic of ScienceShenzhen 518000China Institute of Urban Ecology and Environmental Technology School of Materials and Environmental EngineeringShenzhen Polytechnic UniversityShenzhen 518055China

The biosynthesis of isoprene offers a more sustainable alternative to fossil fuel-based approaches,yet its success has been largely limited to pure organic compounds and the cost remains a *** study proposes a waste-to-wealth strategy for isoprene biosynthesis utilizing genetically engineered *** bacteria to convert organic waste from real food *** impact of organic compounds present in wastewater on *** growth and isoprene production was systematically *** results demonstrated that with filtration pretreatment of wastewater,isoprene yield,and production achieved 115 mg/g COD and 7.1 mg/(L·h),***,even without pretreatment,isoprene yield only decreased by~24%,indicating promising ***,maltose,glycerol,and lactate are effective substrates for isoprene biosynthesis,whereas starch,protein,and acetate do not support *** *** optimum C/N ratio for isoprene production was found to be 8:***,augmenting essential nutrients in wastewater elevated the isoprene yield increased to 159 mg/g *** wastewater biosynthesis significantly reduced the cost(44%–53%decrease,p-valuelueh both sugar fermentation and fossil fuel–based *** study introduced a more sustainable and economically viable approach to isoprene synthesis,offering an avenue for resource recovery from wastewater.

关键词： Wastewater Resource recovery Genetic engineering Biosynthesis Isoprene

Surface iodine and pyrenyl-graphdiyne co-modified Bi catalysts for highly efficient CO_(2) electroreduction in acidic electrolyte

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Nano Research 2024年第4期17卷 2381-2387页

作者： Min Zhang Juan Wang Xin Rong Xiu-Li lu Tong-Bu lu MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

CO_(2) electroreduction to formic acid/formate would contribute to alleviating the energy and climate *** work reports a Bi-based catalyst derived from the in-situ electroreduction of Bi_(2)O_(2)CO_(3) modified with iodine and pyrenyl-graphdiyne(PGDY)on the surface for efficient electroreduction of CO_(2) in acidic electrolyte,with a high partial current density of 98.71 mA·cm^(-2) and high Faradaic efficiency(FE)>90%over the potential range from^(-1).2 to-1.5 V *** hydrogen electrode(RhE),as well as the long-term operational stability over 240 h without degradation in h-type *** results and density function theory calculations show that the synergistic effect of surface iodine and PGDY is responsible for this active and extremely stable process of CO_(2) electroreduction via lowering the energy barriers for formation of*OChO intermediate,suppressing the competitive hER by enhancing the concentration of both K+and CO_(2) at reaction interface,as well as preventing the dissolution and re-deposition of active Bi atoms on surface during catalytic *** work provides new insight into designing highly active and stable electrocatalysts for CO_(2) reduction.

关键词： CO_(2) reduction electrocatalysis Bi-based catalysts acidic electrolyte