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Soliton Solutions to Coupled Integrable Dispersionless Equations

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Communications in Theoretical Physics 2008年第7期50卷 43-47页

作者： YONG Xue-Lin chen yu-fu Department of Mathematics and Physics North China Electronic Power University Beijing 102206 School of Mathematical Science Graduate University of the Chinese Academy of Sciences Beijing 100049 China

In this paper, by introducing a new transformation, the bilinear form of the coupled integrable dispersionless （CID） equations is derived. It will be shown that this bilineax form is easier to perform the standard Hirota process. One-, two-, and three-soliton solutions are presented. furthermore, the N-soliton solutions axe derived.

关键词： Hirota bilinear method coupled integrable dispersionless (CID) equations soliton solutions

Conservation Laws of a Class of Combined Equations

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Communications in Theoretical Physics 2009年第1期51卷 35-38页

作者： ZHANG Zhi-Yong YONG Xue-Lin chen yu-fu School of Mathematical Sciences Graduate University of Chinese Academy of Sciences Beijing 100049 China Department of Mathematics and Physics North China Electronic Power University Beijing 102206 China

In this paper, we investigate conservation laws of a class of partial differential equations, which combines the nonlinear telegraph equations and the nonlinear diffusion-convection equations. Moreover, some special conservation laws of the combined equations are obtained by means of symmetry classifications of wave equations uxx = H （x）utt.

关键词： symmetry conservation law multiplier differential characteristic set

Classification and Approximate Solutions to a Class of Perturbed Nonlinear Wave Equations

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Communications in Theoretical Physics 2009年第11期52卷 769-772页

作者： ZHANG Zhi-Yong chen yu-fu YONG Xue-Lin School of Mathematical Sciences Graduate University of Chinese Academy of Sciences Beijing 100049 China Department of Mathematics and Physics North China Electric Power University Beijing 102206 China

A complete approximate symmetry classification of a class of perturbed nonlinear wave equations isperformed using the method originated from fushchich and ***,large classes of approximate invariantsolutions of the equ... 详细信息

关键词： approximate symmetry Lie reduction approximate solution

Land Use Changes of an Aeolian-Loessial Soil Area in Northwest China: Implications for Ecological Restoration

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Pedosphere 2009年第3期19卷 356-361页

作者： chen yu-fu LIU Yan-Sui WANG Jing YAN Jian-Ping GUO Xu-Dong Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China） Key Laboratory of Land Use Institute of Land Surveying ~ Planning Ministry of Land ＆ Resources Beijing 100035（China）

China has experienced dramatic land use changes over recent decades, with marked environmental and socio-economic consequences. Hengshan County, located in the aeolian-loessial area of Northwest China, was investigated to illustrate land use changes and their implications for environmental and long-term rural economic development. The farmland in Hengshan County significantly decreased during 1990–2003, whereas forest land and grassland increased. The conversion rates of farmland, orchard land, forest land and construction land varied markedly among different periods: 1990–1995, 1995–2000 and 2000–2003. Conversion of orchard land, grassland and construction land was dominant in 1990–1995, whereas the conversion of farmland to forest land mainly occurred in 2000–2003. The results suggested a profound transition in institutional policy and political economy of land management, including implementation of integrated soil erosion control projects, adoption of a market-oriented economy and the ‘Grain-for-Green’ policy, during this period in China. To achieve long-term sustainable land use in Hengshan County, efforts should aim at increasing off-farm income of rural families as well as establishing land-economizing mechanisms to promote land productivity, in addition to conservation measures.

关键词： Hengshan County land management per capita land area policy sustainable land use

Conservation laws of the generalized short pulse equation

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Chinese Physics B 2015年第2期24卷 12-15页

作者：张智勇陈玉福 College of Sciences North China University of Technology School of Mathematical Sciences University of Chinese Academy of Sciences

We show that the generalized short pulse equation is nonlinearly self-adjoint with differential ***,any adjoint symmetry is a differential substitution of nonlinear self-adjointness,and vice ***,the general conservati... 详细信息

关键词： nonlinear self-adjointness with differential substitution adjoint symmetry conservation law

Gradient‑Layered MXene/Hollow Lignin Nanospheres Architecture Design for Flexible and Stretchable Supercapacitors

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Nano-Micro Letters 2025年第2期17卷 447-462页

作者： Haonan Zhang cheng Hao Tongtong fu Dian yu Jane Howe Kaiwen chen Ning Yan Hao Ren Huamin Zhai Jiangsu Provincial Key Lab of Sustainable Pulp and Paper Technology and Biomass Materials NanJing Forestry UniversityNanjing 210037People’s Republic of China Department of Chemical Engineering and Applied Chemistry University of Toronto200 College StreetTorontoON M5S 3E5Canada Department of Materials Science and Engineering University of Toronto184 College StreetTorontoON M5S 3E4Canada College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037People’s Republic of China

With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has *** this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable *** depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene ***,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of *** these strategies effectively enhanced the capacitive performance of the *** addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the *** electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),***,their capacitances were well preserved after 1000 times of 600%stretch-release *** study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.

关键词： Hollow lignin nanospheres MXene Gradient-layered architecture Wrinkled electrodes Stretchable supercapacitors

高速移动铁路货车轴承声信号多普勒效应去除方法

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北京邮电大学学报 2016年第5期39卷 42-46页

作者：陈斌付彧高宝成北京邮电大学自动化学院北京100876

针对货车滚动轴承轨边声学诊断中高速移动带来的声信号频移和频带扩展问题,提出一种基于到达时差和时域插值的多普勒畸变信号矫正方法.通过对轴承运动特性与故障特征频率分析,建立轨边传声器阵列的布放准则,在此基础上通过对阵列检测声... 详细信息

针对货车滚动轴承轨边声学诊断中高速移动带来的声信号频移和频带扩展问题,提出一种基于到达时差和时域插值的多普勒畸变信号矫正方法.通过对轴承运动特性与故障特征频率分析,建立轨边传声器阵列的布放准则,在此基础上通过对阵列检测声信号进行分帧加窗和互相关分析,计算传声器间时延差;引入到达时差技术实时估计故障轴承的移动位置和传播时延,通过时域插值,获得以移动轴承发声时间序列为基准的无时延接收声信号.仿真结果表明,该方法在低信噪比时仍可有效矫正多普勒畸变的声信号,且适用于定转速及变转速场合.

关键词：货车轴承多普勒效应时域插值声源定位

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气孔排数对带排气航行体绕流流动影响研究

工程热物理学报 2018年第9期39卷 1945-1951页

作者：马贵辉陈浮俞建阳哈尔滨工业大学能源科学与工程学院哈尔滨150001

数值研究了航行体垂直出水过程中单排孔排气、双排孔组合排气对贴体气膜及绕流流场的影响。结果表明,相比单排孔方案,双排孔方案孔排间"逆向流动"诱导气膜覆盖后排孔表面,航行体侧向水流对气膜的剪切作用减弱,排气早期气膜形成速度快,... 详细信息

数值研究了航行体垂直出水过程中单排孔排气、双排孔组合排气对贴体气膜及绕流流场的影响。结果表明,相比单排孔方案,双排孔方案孔排间"逆向流动"诱导气膜覆盖后排孔表面,航行体侧向水流对气膜的剪切作用减弱,排气早期气膜形成速度快,空间尺寸大;孔排间表征马蹄涡位置的分离鞍点随模型运动逐渐推进至后排孔前缘,马蹄涡向下游发展过程中在主气膜两侧分割出局部条状气膜;组合排气后排孔近似垂直航行体表面排气,气孔下游较强肾型涡聚拢气膜两侧气体并将其抬离壁面,某些情况下不利于气膜的周向融合。

关键词：水下航行体等压排气单、双排孔流场结构

Management of Benign Tracheal Stenosis by Small-diameter Tube-assisted Bronchoscopic Balloon Dilatation

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Chinese Medical Journal 2015年第10期128卷 1326-1330页

作者： Yi-Lin Liang Guano-Nan Liu Hou-Wen Zheng yu Li Le-cheng chen yu-Yan fu Wen-Tao Li Si-Ming Huang Mei-Ling Yang Department of Respiratory Medicine First Affiliated Hospital of Guangxi Medical UniversityNanningGuangxi 530021China

Background：A limitation of bronchoscopic balloon dilatation （BBD） is that airflow must be completely blocked for as long as possible during the ***,the patient often cannot hold his or her breath for a long period affecting the efficacy of the *** this study,we used an extra-small-diameter tube to provide assisted ventilation to patients undergoing BBD and assessed the efficacy and safety of this ***：Bronchoscopic balloon dilatation was performed in 26 patients with benign tracheal stenosis using an extra-small-diameter *** tracheal diameter,dyspnea index,blood gas analysis results,and complications were evaluated before and after *** analyses were performed by SPSS version 16.0 for Windows （SPSS,Inc.,Chicago,IL,USA）.Results：Sixty-three BBD procedures were performed in 26 *** immediately improved in all patients after *** tracheal diameter significantly increased from 5.5 ± 1.5 mm to 13.0 ± 1.3 mm （P 〈 0.001）,and the dyspnea index significantly decreased from 3.4 ± 0.8 to 0.5 ± 0.6 （P 〈 0.001）.There was no significant change in the partial pressure of oxygen during the operation （before,102.5 ± 27.5 mmHg;during,96.9 ± 30.4 mmHg;and after,97.2 ± 21.5 mmHg;P =0.364）,but there was slight temporary retention of carbon dioxide during the operation （before,43.5 ± 4.2 mmHg;during,49.4 ± 6.8 mmHg;and after,40.1 ± 3.9 mmHg;P 〈 0.001）.Conclusion：Small-diameter tube-assisted BBD is an effective and safe method for the management of benign tracheal stenosis.

关键词： Balloon Dilatation Benign Tracheal Stenosis Bronchoscopy Tube