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Properties of focused Laguerre–Gaussian beam propagating in anisotropic ocean turbulence

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Chinese Physics B 2024年第2期33卷 386-393页

作者：王新光马洋斌袁邱杰陈伟王乐赵生妹 College of Science Nanjing University of Posts and TelecommunicationsNanjing 210003China Institute of Signal Processing and Transmission Nanjing University of Posts and TelecommunicationsNanjing 210003China Key lab.of Broadband Wireless Communication and Sensor Network Technology(Ministry of Education) Nanjing University of Posts and TelecommunicationsNanjing 210003China National lab.ratory of solid State Microstructures Nanjing UniversityNanjing 210093China

We analyze the properties of a focused Laguerre–Gaussian(LG)beam propagating through anisotropic ocean turbulence based on the Huygens–Fresnel *** the Rytov approximation theory,we derive the analytical formula of the channel capacity of the focused LG beam in the anisotropic ocean turbulence,and analyze the relationship between the capacity and the light source parameters as well as the turbulent ocean *** is found that the focusing mirror can greatly enhance the channel capacity of the system at the geometric focal plane in oceanic *** results also demonstrate that the communication link can obtain high channel capacity by adopting longer beam wavelength,greater initial beam waist radius,and larger number of transmission ***,the capacity of the system increases with the decrease of the mean squared temperature dissipation rate,temperature-salinity contribution ratio and turbulence outer scale factor,and with the increase of the kinetic energy dissipation rate per unit mass of fluid,turbulence inner scale factor and anisotropy *** to a Hankel–Bessel beam with diffraction-free characteristics and unfocused LG beam,the focused LG beam shows superior anti-turbulence interference properties,which provide a theoretical reference for research and development of underwater optical communication links using focused LG beams.

关键词： vortex beam orbital angular momentum focusing mirror anisotropic turbulence

Modified electronic structure and enhanced hydroxyl adsorption make quaternary Pt-based nanosheets efficient anode electrocatalysts for formic acid-/alcohol-air fuel cells

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Journal of Energy Chemistry 2024年第5期92卷 142-150页

作者： Fengling Zhao Qiang Yuan Siyang Nie Liang Wu Xun Wang State-Local Joint lab.ratory for Comprehensive Utilization of Biomass Center for R&D of Fine ChemicalsCollege of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025GuizhouChina Key lab.of organic Optoelectronics&Molecular Engineering Tsinghua UniversityBeijing 100084China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Surface/interface engineering of a multimetallic nanostructure with diverse electrocatalytic properties for direct liquid fuel cells is desirable yet ***,using visible light,a class of quaternary Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)ultrathin nanosheets is fabricated and used as high-performance anode electrocatalysts for formic acid-/alcohol-air fuel *** modified electronic structure of Pt,enhanced hydroxyl adsorption,and abundant exterior defects afford Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C high intrinsic anodic electrocatalytic activity to boost the power densities of direct formic acid-/methanol-/ethanol-/ethylene glycol-/glycerol-air fuel cells,and the corresponding peak power density of Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C is respectively 129.7,142.3,105.4,124.3,and 128.0 mW cm^(-2),considerably outperforming Pt/*** in situ Fourier transform infrared reflection spectroscopy reveals that formic acid oxidation on Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C occurs via a CO_(2)-free direct *** functional theory calculations show that the presence of Ag,Bi,and Te in Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)suppresses CO^(*)formation while optimizing dehydrogenation steps and synergistic effect and modified Pt effectively enhance H_(2)O dissociation to improve electrocatalytic *** synthesis strategy can be extended to 43 other types of ultrathin multimetallic nanosheets(from ternary to octonary nanosheets),and efficiently capture precious metals(i.e.,Pd,Pt,Rh,Ru,Au,and Ag)from different water sources.

关键词： Pt-based nanosheets Modifiedelectronic structure Enhanced hydroxyl adsorption Formicacidand alcohol oxidation Direct liquid fuel cells

Microstructure,Corrosion and Mechanical Properties of Medium-Thick 6061-T6 Alloy/T2 Pure Cu Dissimilar Joints Produced by Double Side Friction Stir Z Shape Lap-Butt Welding

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 385-400页

作者： Jiuxing Tang Guoxin Dai Lei Shi Chuansong Wu Sergey Mironov Surendra Kumar Patel Song Gao Mingxiao Wu MOE Key lab.for Liquid-solid Structure Evolution and Materials Processing Shandong UniversityJinan 250061China lab.ratory of Mechanical Properties of Nanoscale Materials and Superalloys Belgorod State UniversityBelgorod 308015Russia School of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China State Grid Henan Electric Power Research Institute Zhengzhou 450052China

A novel double side friction stir Z shape lap-butt welding(DS-FSZW)process was proposed to achieve excellent mechanical properties of Al/Cu medium-thick dissimilar *** influence of welding parameters on weld microstructure and properties of DS-FSZW joint were systematically *** indicated that defect-free medium-thick Al/Cu DS-FSZW joint could be achieved under an optimal welding ***-FSZW joint was prone to form void defects in the bottom of the second-pass *** recrystallization mechanisms at the top and middle of the weld nugget zone(WNZ)were continuous dynamic recrystallization(CDRX)and geometric dynamic recrystallization(GDRX).While the major recrystallization mechanism at the bottom of the WNZ was ***-FSZW joint of the optimal welding condition with 850 r/min-400 mm/min was produced with a continuous thin and crack-free IMCs layer at the Al/Cu interface,and the maximum tensile strength of this joint is 160.57 MPa,which is equivalent to 65.54%of pure Cu base ***,the corrosion resistance of Al/Cu DS-FSZW joints also achieved its maximum value at the optimal welding parameter of 850 r/min-400 mm/*** demonstrates that the DS-FSZW process can simultaneously produce medium-thick Al/Cu joints with excellent mechanical performance and corrosion resistance.

关键词： DS-FSZW Al/Cu dissimilar joint Corrosion behaviour Intermetallic compounds Microstructure Mechanical properties

THE EFFECT OF PHOTO-CROSSLINKING ON THE ORIENTATION STABILITY OF POLYVINYL ALCOHOL CONTAINING 4-NITRO-4′-ALKOXYSTILBENE AND CINNAMYL PENDENT GROUPS

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Chinese Journal of Polymer Science 1997年第2期15卷 154-161页

作者：冯知明林伟平叶成 organic solid lab. Institute of Chemistry Chinese Academy of Sciences Beijing 100080 Department of Physics Northwestern University Evanston IL 60208 USA

Crosslinking is one of the effective routes for improving the orientation stability of poled polymer films. The derivative of polyvinyl alcohol containing 4-nitro-4'-alkoxystilbene and photo-crosslinkable cinnamyl groups as side chains has been synthesized. The in-situ simultaneous photo-crosslinking poling of synthesized polymer films has teen performed, The second order nonlinear optical coefficient d(33) of poled film is 11 pm/V. The SHG measurements show that the break-over temperature of SHG signal is raised obviously after irradiation, its orientation stability is doubled as compared with that of non-crosslinking samples.

关键词： photo-crosslinking in-situ simultaneous photo-crosslinking poling nonlinear optical polymer SHG orientation stability

Synthesis and Fluorescence Quenching of Copolymer Containing3, 4, 9, 10-Perylenetetracarboxyl Diimide Side Chains

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Chinese Chemical Letters 1999年第11期10卷 953-956页

作者： Zhao ZHANG Zhao Bin CHEN Feng Lian BAI Yue Ping ZHANG Yi Ming MO Min ZHENG Xiao Lin YAN Yu hang LI(Department of Chemistry, Shanxi University, Taiyuan 030006)(lab.of organic solid, Institute of Chemistry, Academy Sinica, Beijing 100080) Department of Chemistry Shanxi University Taiyuan 030006 China lab. of organic solid Institute of Chemistry Academy Sinica Beijing 100080 China

A photoluminescence material, copolymer of N-vinylcarbazole (VCz) and N,N'- bisallyl-3, 4. 9, 10-ferylenetetracarboxyl diimide (APTC) chromophores P(VCz-APTC) was synthesized. The fluorescence quenching of P(VCz-APTC)... 详细信息

关键词： 3, 4, 9, 10-perylenetetracarboxyl diimide copolymer fluorescence quenching

Production of Free Amino Acid and Short Peptide Fertilizer from Rapeseed Meal Fermentation Using Bacillus flexus NJNPD41 for Promoting Plant Growth

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Pedosphere 2018年第2期28卷 261-268页

作者： LIU Hongjun ZHONG Xi HUANG Yan QIAO Cece SHAO Cheng LI Rong SHEN Qirong Jiangsu Provincial Key lab.for solid organic Waste Utilization Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization National Engineering Research Center for Organic-based Fertilizers Nanjing Agricultural University

Free amino acids and short peptides(FAPS)that play an important role in plant nutrition can be extracted from rapeseed meal(RSM)by microbial *** enzymolytic activity of one bacterial strain isolated from RSM for the production of FAPS fertilizer(FAPSF)via solid-state fermentation,as well as its detoxification activity for isothiocyanates and oxazolidinethione,was investigated in this *** strain NJNPD41 isolated from RSM piled-soil possessed effective proteolytic activity and was identified as Bacillus flexus on the basis of its morphological,physiological,and biochemical properties,as well as 16S rDNA *** to the uninoculated control,inoculation with the strain NJNPD41 significantly increased the yield of total free amino acids and short peptides by 115%and decreased the content of isothiocyanates and oxazolidinethione by 53%and 60%,respectively,after solid-state *** pot and field experiments showed that FAPSF significantly promoted eggplant growth and enhanced the fruit yield and quality of eggplant compared to the *** conclusion,this study provided a novel method for the high-value utilization of RSM to produce high-quality and low-toxicity FAPSF using the newly isolated strain *** NJNPD41.

关键词： bacterial strain detoxification activity isothiocyanate microbial enzymolysis N pool organic fertilizer solid-statefermentation oxazolidinethione

Bacillus cereus X5 Enhanced Bio-organic Fertilizers Effectively Control Root-Knot Nematodes(Meloidogyne sp.)

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Pedosphere 2013年第2期23卷 160-168页

作者： XIAO Tong-Jian CHEN Fang GAO Chao ZHAO Qing-Yun SHEN Qi-Rong RAN Wei Jiangsu Provincial Key lab.for solid organic Waste Utilization Nanjing Agricultural University

The efficacy of Bacillus cereus X5 as a potential biological control agent against root-knot nematodes was evaluated in vitro by examining second-stage juvenile mortality and egg hatching rate under addition of culture filtrate and in planta by application of bio-organic fertilizers enhanced with B. cereus X5, B. thuringiensis BTG, or Trichoderma harzianum SQR-T037 alone or together in greenhouse and field experiments. The biofumigation of the root-knot nematode-infested soil with organic materials (chicken manure, pig manure and rice straw) alone or in combination with B. cereus X5 was also conducted in greenhouse experiments. In lab.ratory, the filtrate of B. cereus X5 more effectively reduced egg hatching rates during the incubation period for 14 d and more effectively killed the second-stage juvenile during the incubation period of 24 h than that of B. thuringiensis BTG. The highest dry shoot weights for greenhouse tomatoes and field muskmelons were found in both the treatment consisting of the bio-organic fertilizer enhanced with the three biocontrol agents and the treatment consisting of the bio-organic fertilizer enhanced only with B. cereus X5. The two bio-organic fertilizers achieved better nematicidal effects than those enhanced only with B. thuringiensis BTG or T. harzianum SQR-T037. B. cereus X5 also enhanced effect of biofumigation, which resulted in increased plant biomass and reduced nematode counts in the roots and rhizosphere soil. Therefore, these results suggested that biological control of root-knot nematodes both in greenhouses and fields could be effectively achieved by using B. cereus X5 and agricultural wastes.

关键词： biofumigation biological control culture filtrate muskmelon rhizosphere soil

Hybrid-integrated 200 Gb/s REC-DML array transmitter based on photonic wire bonding technology

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Chinese Optics Letters 2024年第8期22卷 64-69页

作者： Yuxin Ma Jie Zhao Tongtong Yang Yipeng Mei Zhenxing Sun Jun Lu Shaobo Li Xiang Ma Xiangfei Chen Key lab.ratory of Intelligent Optical Sensing and Manipulation of the Ministry of Education&National lab.ratory of solid State Microstructures&College of Engineering and Applied Sciences&Institute of Optical Communication Engineering&Nanjing University-Tongding Joint lab.for Large-Scale Photonic Integrated Circuits Nanjing UniversityNanjing 210023China Optical Communication Research and Development Center 54th Research Institute of China Electronics Technology Group CorporationShijiazhuang 050081China

An 8-channel hybrid-integrated chip for 200 Gb/s(8×25 Gb/s)signal transmission has been *** channels are all within the O-band,and with a spacing of 800 *** core of this chip is a monolithic integrated multi-wavelength laser array of 8 directly-modulated distributed feedback(DFB)*** using the reconstruction equivalent chirp technique,multi-wavelength integration and asymmetric phase shift structures are achieved in the laser *** output laser beams of the array are combined by a planar light-wave circuit,which is hybrid-integrated with the laser array by photonic wire *** results of this transmitter chip show good single-mode working of each unit laser,with a sidemode suppression ratio above 50 dB,and the modulation bandwidth is above 20 *** eye diagrams are obtained in the lasers for 25 Gb/s non-return-to-zero modulation,which implies a total 200 Gb/s transmission rate for the whole chip.

关键词： direct modulation laser array reconstruction equivalent chirp photonic wire bonding hybrid integration

NONLINEAR OPTICAL PROPERTIES OF A-SHAPED NITROPYRIMIDINE DERIVATIVES AND ITS POLYMERIC FILMS

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Chinese Journal of Polymer Science 1996年第4期14卷 362-367页

作者：相莹许叶成 organic solid lab. Institute of Chemistry Chinese Academy of Sciences Beijing 100080

Three A-shaped nitropyrimidine derivatives with benzyl or furfuryl as bridge havebeen synthesized. They possess shorter absorption wavelengths (λ_(cut-off))<400 nm) andhigher βμ values (around 10^(-46) esu). The second order nonlinear optical coefficient d_(33) ofpoled BNPMOPMDA/PMMA doped film is 1.2-2.0×10^(-9) esu obtained by in-situ SHGmeasurements. It can be expected that the chromophore-functionalized polymer containinghigher number density of synthesized chromophore as side chain will be the potential blue-light transparent frequency doubling materials.

关键词： Blue-light transparent materials A-shaped compounds Nitropyrimidine derivatives Second harmonic generation Poled polymer