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An Explicit Lower Bound for Blow Up Time in a Class of Nonlinear Wave Equations with Nonlinear Damping and Source Terms

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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 148-154页

作者： xiao-ming peng Ya-dong SHANG Xue-qin WANG School of Statistics and Mathematics Guangdong University of Finance and EconomicsGuangzhou 510320China School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006China College of Mathematics and Informatics South China Agricultural UniversityGuangzhou 510642China

This paper deals with an initial boundary value problem for a class of nonlinear wave equation with nonlinear damping and source terms whose solution may blow up in finite *** explicit lower bound for blow up time is ... 详细信息

关键词： lower bound blow up nonlinear wave equation nonlinear damping nonlinear source

Comparison of laser epithelial keratomileusis and photorefractive keratectomy for the correction of myopia： a meta-analysis

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Chinese Medical Journal 2008年第22期121卷 2331-2335页

作者： CUI Min CHEN xiao-ming LU peng Department of Ophthalmology West China Hospital Sichuan University Chengdu Sichuan 610041 China

Background It is unclear whether a laser epithelial keratomileusis （LASEK） has any significant advantage over a photorefractive keratectomy （PRK） for correcting myopia. We undertook this meta-analysis of randomized controlled trials to examine possible differences in efficacy, accuracy, safety and side-effects between two methods, LASEK and PRK, for correcting myopia. Methods A systematic literature retrieval was conducted in the PubMed, EMBASE, Chinese Bio-medicine Database, and Cochrane Controlled Trials Register to identify potentially relevant randomized controlled trials. The statistical analysis was performed using a RevMan 4.2 software. The results included efficacy outcomes （proportion of eyes with uncorrected visual acuity （UCVA）〉 20/20 at 1 month and 12 months post-treatment）, accuracy outcomes （proportion of eyes within ±0.50 diopters （D） of target refraction at 1 month and 12 months post-treatment）, safety outcomes （loss of 〉2 lines of best spectacle-corrected visual acuity （BSCVA） at 〉 6 months post-treatment）, mean pain scores on day 1 post-treatment, and mean corneal haze scores at 6 and 12 months post-treatment. Results Seven articles describing a total of 604 eyes with myopia from 0 to -9.0 D were identified in this meta-analysis. The combined results showed that the efficacy and accuracy outcomes between the two groups at 1 month and 12 months post-treatment were comparable. No patient lost 〉 2 lines of BSCVA at 〉 6 months post-treatment in four relevant trials. Compared with PRK, LASEK did not relieve discomfort on day 1 post-treatment or reduce corneal haze intensity at 6 and 12 months post-treatment. Conclusions According to the available data, LASEK does not appear to have any advantage over PRK for correcting myopia from 0 to -9.0 D. This meta-analysis focuses mainly on the comparison of the early, mid-term and mid-long term results of the two methods. Additional studies to compare the long-term （〉one year） results should be considered.

关键词： laser epithelial keratomileusis photorefractive keratectomy myopia meta-analysis

Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao peng Yuefeng Song Ihar Razanau Juanxiu xiao Wei xiao Di Hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Methane Electrochemical conversion Reaction mechanism Catalyst design Electrode Electrocatalysis

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： xiao Xiang Feng Gao Yu-Gui peng peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Diagnosis and management of first branchial fistula: a study of 12 cases

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Journal of Otology 2008年第1期3卷 51-55页

作者： OU Yong-kang, XU Yao-dong, LIU Xiang, HUANG xiao-ming, peng Jie-ren, ZHENG Yi-qing Department of Otorhinolaryngology&Head-Neck Surgery, The 2nd Affiliated Hospital of Sun Yat-sen University Department of Otorhinolaryngology&Head–Neck Surgery The 2nd Affiliated Hospital of Sun Yat–sen University

Objectives To report authors’ experiences in the diagnosis and treatments of congenital first branchial fistula (congenital auriculocervical fistula). Materials and Methods Twelve cases of congenital first branchial fistula were reviewed. Of these, 8 underwent fistulectomy with facial nerve dissection and partial parotidectomy and 4 underwent simple fistulectomy. Results The inner openings (upper opening) of fistulae lay in the following sites: inferioposterior wall at the junction of cartilaginous and bony segments of the auricular canal and inferior wall of cartilaginous auricular canal. The outer openings(lower opening) lay along the anterior border of upper sternocleidomastoid muscle, at the mastoid tip and posterior to the mandibular angle. Complete fistulae resection was achieved in all but one case. Eleven cases were followed for 5 year with no recurrence. Recurrence occurred in 1 case 6 months after the primary surgery and revision surgery was performed. Conclusions Pre-operative radiography for the location and course of the fistula is crucial for successful fistula resection, especially in cases with past infections. Facial nerve dissection should be done routinely for deeply located fistulae.

关键词： Congenital Malformation First Branchia Auriculocervical Fistula Diagnosis Surgery

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直流电场作用下油中水滴的破裂时间特征

工程热物理学报 2017年第8期38卷 1707-1713页

作者：罗小明闫海鹏王静何利民中国石油大学(华东)山东省油气储运安全省级重点实验室青岛266580 中石化石油工程设计有限公司东营257026

采用显微实验与理论分析相结合的方法,对直流电场作用下水滴破裂前的拉伸过程及其时间特征进行了系统研究。结果表明,电毛细数和表面活性剂浓度是影响水滴拉伸过程的关键因素,而油水黏度比和电导率比的影响并不显著。拉伸时间对低电毛... 详细信息

采用显微实验与理论分析相结合的方法,对直流电场作用下水滴破裂前的拉伸过程及其时间特征进行了系统研究。结果表明,电毛细数和表面活性剂浓度是影响水滴拉伸过程的关键因素,而油水黏度比和电导率比的影响并不显著。拉伸时间对低电毛细数和高表面活性剂浓度体系更为敏感。在实验范围内,直流电场作用下球形水滴经拉伸并破裂的最小时间为10 ms。基于此,提出了一种可有效提高水滴静电聚并效率并抑制电分散现象的脉冲电场设计方法。

关键词：直流电场水滴破裂瞬态响应时间特征

用于级连EDFA增益谱平坦的滤波器透过谱设计的迭代算法

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中国激光 2001年第3期28卷 265-268页

作者：肖艳红厉群韩岩刘小明彭江得清华大学电子工程系北京100084

针对在两段掺铒光纤中插入滤波器实现宽带 (35nm)增益平坦的滤波器透过谱的设计问题 ,提出了一种新的迭代算法。其原理是利用放大器的均匀展宽特性和级连放大器自动增益补偿的特性。在每次迭代中 ,都取要求带宽内增益 (分贝数 )的平均... 详细信息

针对在两段掺铒光纤中插入滤波器实现宽带 (35nm)增益平坦的滤波器透过谱的设计问题 ,提出了一种新的迭代算法。其原理是利用放大器的均匀展宽特性和级连放大器自动增益补偿的特性。在每次迭代中 ,都取要求带宽内增益 (分贝数 )的平均值为参考轴 ,在增益比该轴高的波长范围内再附加一与增益谱反对称的损耗谱。而增益低于参考值的波长处则会得到自动的增益补偿。模拟计算结果表明 ,用该方法得到的滤波谱能使放大器的增益平坦在原放大器可能得到的最高增益水平 ,同时因滤波器的引入带来的噪声特性恶化也最小。

关键词：掺饵光放大器增益谱平坦滤波器谱设计迭代算法

Effect and mechanism of EOP on diabetic mice induced by alloxan

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Effect and mechanism of EOP on diabetic mice induced by allo...

Fiber Null Coupler with Ultra-High Splitting Ratio for Optic Switching and Add-Drop Multiplexing

中国药理学会第十次全国学术会议

作者： XIN xiao-ming,Qiu Li-peng,WANG Hao,Gao Yun-sheng (Pharmaceutical college,Taishan Medical College,Taian 271016,China)

Aim In order to investigate the hypoglycemic effect of the eucommia ulmoides oliv polysaccharides on diabetes mellitus mices caused by Alloxan,in order to provide the basis theory for eucommia’s further development and the *** Hyperglycemic model of mice was made by intraperitoneal injection of alloxan(250 mg·kg),which destroys their pancreatic islet *** the blood glucose of the mice with blood glucose monitoring,blood glucose levels higher than 10.0 mmol·L were the successful diabetic *** mice were randomly divided into 6 teams by weights,and each group has 8 *** dose of physiological saline, xiao ke wan,low dose(100 mg·kg),medium dose(200 mg·kg) and high dose(400 mg·kg) were given to mice orally by weight(ig),administered orally for ten *** the end of the fasting administration the mice can not help but water 3 *** the blood glucose levels and weight again,after taken the blood from eyeball,the mice were sacrificed for thymus and spleen,then calculated their ***,measuring the index of MDA,SOD in blood,and NO,NOS in the *** the above indexs,observate weather the Eucommia ulmoides oliv polysaccharides have the hypoglycemic effect on diabetes mellitus mices caused by *** Eucommia ulmoides oliv polysaccharides can be effective decrase the blood glucose of diabetes mellitus mice caused by *** with the model group,Eucommia the polysaccharide group of blood glucose and weight loss reduction,thymus index and the index spleen have been increased,MDA,NO lower,and SOD,NOS increased. Conclusion Eucommia ulmoides oliv polysaccharides can decrase the blood glucose of diabetes mellitus mice caused by Alloxan on certen degree.

关键词： Eucommia ulmoides oliv polysaccharides(EOP) Alloxan Hypoglycemic Effect

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Fiber Null Coupler with Ultra-High Splitting Ratio for Optic...