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Absorptive Nonlinearity in Er-Doped Optical Fiber

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Wuhan University Journal of Natural Sciences 1999年第2期4卷 56-59页

作者： Song, Qian li, ji-xing Zhang, Yuan-cheng Wuhan Univ Wuhan China

Optical absorptive nonlinearity in Er doped optical fiber has been discussed and measured at the window wavelength 1.55 μm for optical communications firstly. It is proposed that the mechanism of this absorptive nonlinearity is the induced absorption. The first order nonlinear absorptive coefficient and the imaginary part and the complex value of the third order susceptibility at that wavelength are obtained from the measured absorptive nonlinearity.

关键词： optical nonlinearity Er doped fiber optical absorption

缸盖-缸垫-机体联合仿真在某产品开发中的应用

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内燃机与配件 2024年第10期 14-17页

作者：李连升蔡强李兴济高进崔海冰内燃机与动力系统全国重点实验室潍柴动力股份有限公司山东潍坊261061

缸盖和机体组件作为发动机的本体支撑件,工作过程中承受复杂的机械载荷和热负荷,其可靠性直接决定了发动机的使用寿命。因此针对缸盖和机体在产品设计开发中需要进行详尽的评估验证,保证结构设计的合理性与可靠性。本文介绍了产品设计... 详细信息

缸盖和机体组件作为发动机的本体支撑件,工作过程中承受复杂的机械载荷和热负荷,其可靠性直接决定了发动机的使用寿命。因此针对缸盖和机体在产品设计开发中需要进行详尽的评估验证,保证结构设计的合理性与可靠性。本文介绍了产品设计阶段针对缸盖、机体设计与缸垫联合仿真的评估方法,结合某产品开发过程对该仿真方法进行了详细阐述。根据产品后续试验结果,对仿真计算结果进行了对标验证,确认了联合仿真方法的合理性和有效性。

关键词：缸盖机体联合仿真

Robust Delay-dependent H∞ Consensus Control for Multi-agent Systems with Input Delays

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自动化学报 2014年第11期40卷 2556-2562页

作者： li Zhen-xing ji Hai-Bo Department of Automation University of Science and Technology of China Hefei 230027 China

This paper investigates the consensus control for multi-agent systems subject to external disturbances, input delays and model uncertainties of networks. By defining an appropriate controlled output, we transform this question into a robust H_∞ control problem. Then, we give two criteria to judge the consensusability of closed-loop multi-agent systems and present a cone-complementary linearization algorithm to get the state feedback controller's parameters. Finally, numerical examples are given to show the effectiveness of the proposed consensus protocols.

关键词：多代理系统控制输出时滞相关延迟输入状态反馈控制器线性化算法不确定性

Nitrogen-doped titanium dioxide/schwertmannite nanocomposites as heterogeneous photo-Fenton catalysts with enhanced efficiency for the degradation of bisphenol A

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Journal of Environmental Sciences 2024年第9期143卷 1-11页

作者： xing-xing Qiao Yu-Hang Xu Xiang-ji liu Sai-Le Chen Zhou Zhong Ya-Feng li jian Lü Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China State Key Laboratory of Photocatalysis on Energy and Environment Fuzhou UniversityFuzhou 350116China

Potential health risks related to environmental endocrine disruptors(EEDs)have aroused research hotspots at the forefront of water treatment ***,nitrogen-doped titanium dioxide/schwertmannite nanocomposites(N-TiO_(2)/SCH)have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo-Fenton *** to the sustainable Fe(Ⅲ)/Fe(Ⅱ)conversion induced by photoelectrons,as-prepared N-TiO_(2)/SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A(BPA;ca.100% within 60 min under visible irradiation)in a wide pH range of 3.0-7.8,which is significantly higher than that of the pristine schwertmannite(ca.74.5%)or N-TiO_(2)(ca.10.8%).In this photo-Fenton system,the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical(·OH)and singlet oxygen(^(1)O_(2)).Moreover,the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical *** work not only provides a feasible means for the development of novel heterogeneous photo-Fenton catalysts,but also lays a theoretical foundation for the potential application of mineral-based materials in wastewater treatment.

关键词： Titanium dioxide Schwertmannite Fenton reaction Environmental endocrine disruptors Photocatalysis

In-situ embedded ultrafine Bi_(12)O_(17)Br_(2)nanotubes in MOF-derived hierarchical porous carbon for enhanced photocatalytic CO_(2)conversion to CO

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Journal of Materials Science & Technology 2024年第4期171卷 47-53页

作者： xing Sun Mengxia ji Yi Zhang Qingzeng xing Zihan liu Nianhua liu Emmanuel Nkudede Huaming li Sheng Yin jiexiang Xia School of Chemistry and Chemical Engineering Institute for Energy ResearchJiangsu UniversityZhenjiang 212013China Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Provincial Key Laboratory of Resources Chemistry of Salt LakesQinghai Institute of Salt LakesChinese Academy of SciencesXining 81008China

Increasing the utilization efficiency of photogenerated electrons is highly recognized as one of the ef-ficient approaches to boost the photocatalytic CO_(2)conversion ***,ZIF-67-derived porous carbon(PC)material was employed for the construction of PC@ultrafine Bi_(12)O_(17)Br_(2)nanotubes(PC@BOB NTs)composites through a facile solvothermal synthesis in order to optimize the use of excited elec-trons in the BOB *** characterization results revealed that the introduction of PC material achieved a faster charge separation rate in the PC@BOB composites,ensuring more photogener-ated electrons participate in the CO_(2)adsorption and activation ***,the pore structures of ZIF-67-derived PC material provided abundant confined spaces for the enrichment of CO_(2)***-ter 5 h of Xenon lamp irradiation,PC@BOB composites exhibited obviously increased photocatalytic CO_(2)reduction activity in the pure *** the addition amount of PC was 5 wt%,the PC@BOB-2 com-posite showed the highest CO evolution rate of 359.70μmol/g,which was 2.95 times higher than that of the pure BOB *** work provides some independent insights into the applications of Metal-Organic Framework(MOF)-derived hierarchical porous structures to strengthen the CO_(2)enrichment,as well as the excited charge utilization efficiency,thus achieving a high solar-to-fuel conversion efficiency.

关键词： Bi_(12)O_(17)Br_(2)nanotubes Hierarchical porous structure CO_(2)enrichment Charge separation CO_(2)photoreduction

Surgical approaches to correct corneal astigmatism at time of cataract surgery: a mini-review

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1370-1374页

作者： Xiao-Lei Yin Zhi-Yang ji Xiu-Xin li Xue-Mei liang Shu-xing ji Department of Ophthalmology the 305 Hospital of PLABeijing 100017China Department of Ophthalmology Daping HospitalArmy Medical UniversityChongqing 400042China Department of Medical Administration the 305 Hospital of PLABeijing 100017China

Among refractive errors,astigmatism is the most common optical aberration,where refraction changes in different meridians of the *** causes blurred vision at any distance and includes corneal,lenticular,and retinal *** surgery used to cause a progressive increase in the pre-exisiting corneal astigmatism because of creating a surgically induced astigmatism,for example,a large size surgery *** development of surgical techniques during last decades has made cataract surgery interchange to treat preoperative corneal astigmatism at time of ***,three surgical approaches can be *** placing a sutureless clear corneal incision on the steep meridian of the cornea,a preoperative corneal astigmatism less than 1.0 D can be *** or paired peripheral corneal relaxing incisions(PCRIs)provide 1.0-3.0 D corneal astigmatism *** are typically used for treating 1.0-1.5 D of regular corneal astigmatism,if more than 2.0 D,the risk of overcorrection and irregular astigmatism is *** toric intraocular lenses(IOLs)are unavailable in markets,PCRIs are still a reasonable option for patients with up to 3.0 D of pre-existing corneal *** IOLs implantation can correct 1.0-4.5 D of corneal *** IOLs are approved to correct a high degree of corneal astigmatism with cylinder power up to 12.0 *** approaches can be used alone or in combination.

关键词： cornea astigmatism cataract surgery peripheral corneal relaxing incisions toric intraocular lens

Seasonal Variation of the Sea Surface Temperature Growth Rate of ENSO

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Advances in Atmospheric Sciences 2024年第3期41卷 465-477页

作者： Xinyi xing Xianghui FANG Da PANG Chaopeng ji Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Shanghai Frontiers Science Center of Atmosphere-Ocean Interaction Shanghai 200438China Shanghai Key Laboratory of Ocean-land-atmosphere Boundary Dynamics and Climate Change Fudan UniversityShanghai 200438China

El Ni?o–Southern Oscillation(ENSO) exhibits a distinctive phase-locking characteristic, first expressed during its onset in boreal spring, developing during summer and autumn, reaching its peak towards winter, and decaying over the next spring. Several studies have demonstrated that this feature arises as a result of seasonal variation in the growth rate of ENSO as expressed by the sea surface temperature(SST). The bias towards simulating the phase locking of ENSO by many state-of-the-art climate models is also attributed to the unrealistic depiction of the growth rate. In this study, the seasonal variation of SST growth rate in the Ni?o-3.4 region(5°S–5°N, 120°–170°W) is estimated in detail based on the mixed layer heat budget equation and recharge oscillator model during 1981–2020. It is suggested that the consideration of a variable mixed layer depth is essential to its diagnostic process. The estimated growth rate has a remarkable seasonal cycle with minimum rates occurring in spring and maximum rates evident in autumn. More specifically, the growth rate derived from the meridional advection(surface heat flux) is positive(negative) throughout the year. Vertical diffusion generally makes a negative contribution to the evolution of growth rate and the magnitude of vertical entrainment represents the smallest contributor. Analysis indicates that the zonal advective feedback is regulated by the meridional immigration of the intertropical convergence zone, which approaches its southernmost extent in February and progresses to its northernmost location in September, and dominates the seasonal variation of the SST growth rate.

关键词： SST growth rate intertropical convergence zone zonal advective feedback mixed layer depth ENSO seasonal variation

Rapid Modeling and Finite Element Analysis of Missile Stiffener

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Computer Aided Drafting,Design and Manufacturing 2015年第3期25卷 31-38页

作者： WANG Tian XI Ping li ji-xing School of Mechanical Engineering and Automation Beihang University

Stiffener is the important missile structure to ensure the structural strength of the missile. In order to improve the design efficiency and the quality of the missile stiffener, the methods of missile stiffener rapid modeling and analysis are proposed. First, the problems of traditional manual modeling of the stiffener are analyzed. According to the problems and actual requirement of modeling, volume decomposition method is used to divide the stiffener into the upper section, the lower section and the web in order for feature analysis and parameter extraction. Then based on the parameters the basic unit decomposed above is created for Boolean operation to establish the stiffener. Finally, a rapid stiffener modeling and analysis program were developed based on UG Open API, the modeling and analysis result validates the feasibility of the method.

关键词： rapid modeling stiffener finite element analysis UG open API

Impact of the Political Risk on Food Reserve Ratio:Evidence Across Countries

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Journal of Systems Science & Complexity 2024年第5期37卷 2071-2103页

作者： xing Kai li Shang YANG Xiaoguang School of Economics&Management Nanchang University Department of Statistics and Data Science National University of Singapore Academy of Mathematics and Systems Science Chinese Academy of Sciences University of Chinese Academy of Sciences

Using an unbalanced panel data covering 75 countries from 1991 to 2019, the authors explore how the political risk impacts on food reserve ratio. The empirical findings show that an increasing political risk negatively affects food reserve ratio, and the same effects hold for both internal risk and external risk. Moreover, the authors find that the increasing external or internal risks both negatively affect food production and food exports, but external risk does not significantly impact food imports and it positively impacts food consumption, while internal risk negatively impacts food imports and food consumption. The results suggest that most governments have difficulty raising subsequent food reserve ratios in face of an increasing political risk, no matter if it is an internal risk or an external risk although the mechanisms behind the impacts are different.

关键词： External risk food reserve ratio internal risk political risk