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Time-Delay Signature of Chaotic Vertical-Cavity Surface-Emitting Lasers with Polarization-Rotated Optical Feedback

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Chinese Physics Letters 2011年第1期28卷 98-101页

作者： XIANG Shui-Ying PAN Wei yan lian-shan LUO Bin ZOU Xi-Hua JIANG Ning WEN Kun-Hua Center for Information Photonics and Communications Southwest Jiaotong University Chengdu 610031

To quantitatively evaluate the time-delay （TD） signatures of chaotic signals generated by vertical-cavity surface- emitting lasers （VCSELs） with polarization-rotated optical feedback （PROF）, we propose four cases of resolution coefficients R based on correlation functions. The resolution coefficient characteristics for the x-polarization （XP） mode, g-polarization （YP） mode and the total output are considered. The dependences of R on the feedback strength and feedback delay are discussed and compared carefully. The two-dimensional maps of R show that the TD signatures for the single polarization mode （i.e., XP or YP mode） are much more difficult to retrieve than those for the total output in the entire parameter space. Thus, by using single polarization mode as a chaotic carrier, the TD signatures are extremely difficult to be identified, which contributes a lot in the security-enhanced VCSELs-based chaotic optical communication systems.

关键词： Optics quantum optics and lasers

Effects of impregnation sequence on the NH_(3)-SCR activity and hydrothermal stability of a Ce-Nb/SnO_(2) catalyst

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Journal of Environmental Sciences 2024年第4期138卷 450-457页

作者： Ying Zhu Wenpo shan Zhihua lian Jingjing Liu yan Zhang Hong He Center for Excellence in Regional Atmospheric Environment and Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control Ningbo Urban Environment Observation and Research StationInstitute of Urban EnvironmentChinese Academy of SciencesNingbo 315800China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Hydrothermal stability is crucial for the practical application of deNO_(x)catalyst on diesel vehicles,for the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR).SnO_(2)-based materials possess superior hydrothermal stability,which is attractive for the development of NH_(3)-SCR *** this work,a series of Ce-Nb/SnO_(2)catalysts,with Ce and Nb loading on SnO_(2)support,were prepared by impregnation *** was found that,the NH_(3)-SCR activities and hydrothermal stabilities of the Ce-Nb/SnO_(2)catalysts significantly varied with the impregnation sequences,and the Ce-Nb(f)/SnO_(2) catalyst that firstly impregnated Nb and then impregnated Ce exhibited the best *** characterization results revealed that CeNb(f)/SnO_(2)possessed appropriate acidity and redox ***,the strong synergistic effect between Nb and Sn species stabilized the structure and maintained the dispersion of acid *** study may provide a new understanding for the effect of impregnation sequence on activity and hydrothermal stability and a new environmental-friendly NH_(3)-SCR catalyst with potential applications for NO_(x)removal from diesel and hydrogenfueled engines.

关键词： NO_(x)emission control NH_(3)-SCR Hydrothermal stability Ce-Nb/SnO_(2)catalyst Impregnation sequence

Quantifying Information Flow between Two Chaotic Semiconductor Lasers Using Symbolic Transfer Entropy

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Chinese Physics Letters 2012年第3期29卷 48-51页

作者： LI Nian-Qiang PAN Wei yan lian-shan LUO Bin XU Ming-Feng TANG Yi-Long Center for Information Photonics&Communications School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 610031

Symbolic transfer entropy(STE)is employed to quantify the dominant direction of information flow between two chaotic-semiconductor-laser time *** information flow in unidirectionally and bidirectionally coupled systems was analyzed *** results show that the dependence relationship can be revealed if there exists any coupling between two chaotic semiconductor *** importantly,in both unsynchronized and good synchronization regimes,the STE can be used to quantify the direction of information flow between the lasers,although the former case leads to a better *** results thus establish STE as an effective tool for quantifying the direction of information flow between chaotic-laser-based systems.

关键词： synchronization laser chaotic

Thermal tuning of chirped SOI sidewall grating for tunable wavelength, delay, and bandwidth

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Optoelectronics Letters 2021年第4期17卷 205-208页

作者： DING Jia-yue ZOU Xi-hua ZOU Fang PAN Wei yan lian-shan LUO Bin Center for Information Photonics&Communications School of Infonnation Science ami TechnologySouthwest Jiaotong UniversityChengdu 611756China

In this work, we design a silicon-on-insulator(SOI) sidewall grating with tunable wavelength, delay, and bandwidth through thermal tuning. Incorporating uniform sidewall corrugations and a linearly chirped rib waveguide, the thermo-optic effect imposed on chirped rib waveguide changes the effective refractive index, due to the resultant of the temperature gradient. Consequently, tunable wavelength, delay, and bandwidth in SOI sidewall grating are achieved. In the numerical simulations, the designed SOI grating is demonstrated with a tunable wavelength from 1 560.7 nm to 1 561.9 nm, a tunable delay from 0 to 38 ps, and a tunable bandwidth from 1 nm to 1.5 nm.

关键词： tunable tuning SOI

Gain Improvement of Fiber Parametric Amplifier via the Introduction of Standard Single-Mode Fiber for Phase Matching

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Chinese Physics Letters 2013年第7期30卷 96-98页

作者： ZHU Hong-Na LUO Bin PAN Wei yan lian-shan ZHAO Jian-Peng WANG Ze-Yong GAO Xiao-Rong School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031 Center for Information Photonics and Communications Southwest Jiaotong UniversityChengdu 610031

We investigate and experimentally demonstrate the gain improvement of single-pump fiber parametric amplifiers by using a suitable length of standard single-mode fiber(SSMF)inserted between two high-nonlinear fibers(HNLFs).The SSMF with different dispersion properties from the HNLF is employed for phase matching of the parametric processes,and the signal gain is improved as compared with the absence of the SSMF with experiment ***,the effect of the input pump power and the fiber length of the SSMF on the output signal gain are discussed with experimental investigation.

关键词： fiber pump SSM

Isotopic dependence of the yield ratios of light fragments from different projectiles and their unified neutron skin thicknesses

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Nuclear Science and Techniques 2024年第3期35卷 228-236页

作者： Ting-Zhi yan shan Li School of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(every third isotopes)+112 Sn for full reduced impact parameters using the isospin-dependent quantum molecular dynamics(IQMD)*** neutron and proton density distributions and root-mean-square radii of the reaction systems were obtained using the Skyrme-Hartree-Fock model,which was used for the phase space initialization of the projectile and target in *** defined the unified neutron skin thickness asΔRnp=^(1∕2) n−^(1∕2)p,which was negative for neutron-deficient *** unifiedΔRnp values for nuclei with the same relative neutron excess from different isotopic chains were nearly equal,except for extreme neutron-rich isotopes,which is a type of scaling *** yield ratios of the three isotopic chain-induced reactions,which depended on the reduced impact parameter and unified neutron skin thickness,were *** results showed that both R(n/p)and R(^(3)H∕^(3)He)decreased with a reduced impact parameter for extreme neutron-deficient isotopes;however,they increased with reduced impact parameters for extreme neutron-rich isotopes,and increased with theΔRnp of the projectiles for all reduced impact *** addition,a scaling phenomenon was observed betweenΔR np and the yield ratios in peripheral colli-sions from different isotopic chain projectiles(except for extreme neutron-rich isotopes).Thus,R(n/p)and R(^(3)H∕^(3)He)from peripheral collisions were suggested as experimental probes for extracting the neutron or proton skin thicknesses of non-extreme neutron-rich nuclei from different isotopic chains.

关键词： Exotic nuclei Unified neutron skin thickness Yield ratios IQMD

Influence of Incomplete Soil Plugs on Bearing Capacities of Bucket Foundations in Clay

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China Ocean Engineering 2024年第1期38卷 144-155页

作者： LI Hui-shan LIU Run yanG Xu lian Ji-jian State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China Institute of Marine Energy and Intelligent Construction Tianjin University of TechnologyTianjin 300384China

Due to the uneven seabed and heaving of soil during pumping,incomplete soil plugs may occur during the installation of bucket foundations,and the impacts on the bearing capacities of bucket foundations need to be *** this paper,the contact ratio(the ratio of the top diameter of the soil plug to the diameter of the bucket)and the soil plug ratio(the ratio of the soil heave height to the skirt height)are defined to describe the shape and size of the incomplete soil ***,finite element models are established to investigate the bearing capacities of bucket foundations with incomplete soil plugs and the influences of the contact ratios,and the soil plug ratios on the bearing capacities are *** results show that the vertical bearing capacity of bucket foundations in homogeneous soil continuously improves with the increase of the contact ***,in normally consolidated soil,the vertical bearing capacity barely changes when the contact ratio is smaller than 0.75,while the bearing capacity suddenly increases when the contact ratio increases to 1 due to the change of failure *** contact ratio hardly affects the horizontal bearing capacity of bucket ***,the moment bearing capacity improves with the increase of the contact ratio for small aspect ratios,but hardly varies with increasing contact ratio for aspect ratios larger than ***,the reduction coefficient method is proposed based on this analysis to calculate the bearing capacities of bucket foundations considering the influence of incomplete soil *** comparison results show that the proposed reduction coefficient method can be used to evaluate the influences of incomplete soil plug on the bearing capacities of bucket foundations.

关键词： bucket foundation incomplete soil plug uniaxial bearing capacity contact ratio soil plug ratio

Detection of carboxyhemoglobin in patients with hepatic encephalopathy due to hepatitis B virus-related cirrhosis

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Chinese Medical Journal 2012年第22期125卷 3991-3996页

作者： SUN Xiao-yu DUAN Zhi-jun LI yan-lian CHANG Qing-shan Dalian Med Univ Affiliated Hosp 1 Dept Gastroenterol Dalian 116011 Liaoning Peoples R China Dalian Med Univ Affiliated Hosp 1 Dept Lab Dalian 116011 Liaoning Peoples R China Dalian Infect Dis Hosp Intens Care Unit Dalian 116001 Liaoning Peoples R China

Background The heme oxygenase/carbon monoxide （HO/CO） system plays an important role in the development of hepatic fibrosis. The level of the HO/CO can be directly obtained by determining the carboxyhemoglobin （COHb） level. The aims of this study were to reveal the significance of COHb in patients with hepatitis B virus-related cirrhosis （HBC） complicated by hepatic encephalopathy （HE）, and to further investigate the influence of the HO/CO pathway on the end-stage cirrhosis, hoping to find a reliable indicator to evaluate the course of HBC. Methods According to the diagnostic criteria, 63 HBC inpatients with HE were enrolled in group H. Patients regaining awareness with current therapies were categorized into group P-H. Comparisons were made with a control group （group N） consisting of 20 health volunteers. The levels of COHb, partial pressure of oxygen （PaO2） and oxygen saturation （SaO2） were determined by arterial blood gas analysis method. The incidences of hepatorenal syndrome （HRS）, upper gastrointestinal bleeding, esophagogastric varices and spontaneous bacterial peritonitis （SBP） in group H were recorded. COHb levels in different groups were compared, and the correlations of COHb levels with HE grades （I, II, III, and IV）, PaO2, SaO2 and hypoxemia were analyzed. Results The COHb level in group P-H （（1.672＋0.761）%） was significantly higher than that in group N （（0.983±0.231）%）（P 〈0.01 ）, and the level in group H （（2.102±1.021）%） was significantly higher than groups P-H and N （P 〈0.01 ）. A positive correlation was observed between the COHb concentration and the grade of HE （rs=0.357, P=-0.004）. There were no significant differences of COHb levels between HE patients with and without complications such as esophagogastric varices （（2.302±1.072）% vs. （1.802±1.041）%, P 〉0.05） or the occurrence of SBP （（2.960±0.561）% vs. （2.030±1.021）%, P 〉0.05）. Compared with HE patients with HRS, the level of COHb was significantly higher in HE patients without HRS （（2.502±1.073）

关键词： hepatitis B-related cirrhosis hepatic encephalopathy carboxyhemoglobin

Interface sites on vanadia-based catalysts are highly active for NO_(x) removal under realistic conditions

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Journal of Environmental Sciences 2024年第2期136卷 523-536页

作者： Zhihui Lv Guangzhi He Wenshuo Zhang Jingjing Liu Zhihua lian yang yang Zidi yan Guangyan Xu Wenpo shan Yunbo Yu Hong He State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Regional Atmospheric Environment and Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000China Ningbo Research Center for Urban Environment Chinese Academy of SciencesNingbo 315800China

TiO_(2)-supported V_(2)O_(5)catalysts are commonly used in NO_(x)reduction with ammonia due to their robust catalytic *** these catalysts,it is generally considered that the active species are mainly derived from the vanadia species rather than the intrinsic structure of V-O-Ti entities,namely the interface *** reveal the role of V-O-Ti entities in NH_(3)-SCR,herein,we prepared TiO_(2)/V_(2)O_(5)catalysts and demonstrated that V-O-Ti entities were more active for NO_(x)reduction under wet conditions than the V sites(V=O)working *** the V-O-Ti entities,kinetic measurements and first principles calculations revealed that NH_(3)activation exhibited a much lower energy barrier than that on V=O *** wet conditions,the V-O-Ti interface significantly inhibited the transformation of V=O to V-OH sites thus benefiting NH_(3)*** wet conditions,meanwhile,the migration of NH_(4)^(+)from Ti site neighboring the V-O-Ti interface to Ti site of the V-O-Ti interface was exothermic;thus,V-O-Ti entities together with neighboring Ti sites could serve as channels linking NH_(3)pool and active centers for activation of NH_(4)^(+).This finding reveals that the V-O-Ti interface sites on V-based catalysts play a crucial role in NO_(x)removal under realistic conditions,providing a new perspective on NH_(3)-SCR mechanism.

关键词： NO_(x)removal Vanadia-based catalysts V-O-Ti entities Interface sites Reaction mechanism