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Breathers and solitons for the coupled nonlinear Schrodinger system in three-spine α-helical protein

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Chinese Physics B 2021年第10期30卷 231-238页

作者： Xiao-Min Wang peng-fei li Department of Physics Taiyuan Normal UniversityJinzhong 030619China Institute of Computational and Applied Physics Taiyuan Normal UniversityJinzhong 030619China

We mainly investigate the variable-coefficient 3-coupled nonlinear Schrodinger(NLS)system,which describes soli- ton dynamics in the three-spineα-helical protein with inhomogeneous *** variable-coefficient NLS equation is transformed into the constant coefficient NLS equation by similarity transformation *** Hirota method is used to solve the constant coefficient NLS equation,and then we get the one-and two-breather solutions of the variable-coefficient NLS *** results show that,in the background of plane waves and periodic waves,the breather can be transformed into some forms of combined soliton *** influence of different parameters on the soliton solution and the collision between two solitons are discussed by some graphs in *** results are helpful to study the soliton dynamics inα-helical protein.

关键词： breather soliton nonlinear Schrodinger system a-helical protein

Existence of Positive Solutions to a Fractional-Kirchhoff System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 225-240页

作者： peng-fei li Jun-hui Xie Dan Mu School of Mathematics and Statistics Hubei Minzu UniversityEnshi445000China

LetΩbe a bounded smooth domain in RN(N≥3).Assuming that 00 are constants,we consider the existence results for positive solutions of a class of fractional elliptic system below,{(a+b[u]^(2)_(s))(-Δ)^(s)u=vp+h_(1)(x,u,v,▽u,▽v),x∈Ω,(-Δ)^(s)v=u^(q)+h_(2)(x,u,▽,▽u,▽v),x∈Q,u,v>0,x∈Ω,u=v=0,x∈RN\Ω.Under some assumptions of hi(x,u,v,▽u,▽v)(i=1,2),we get a priori bounds of the positive solutions to the problem(1.1)by the blow-up methods and rescaling *** on these estimates and degree theory,we establish the existence of positive solutions to problem(1.1).

关键词： fractional-Kirchhoff system a priori bounds degree theory positive solution

Synthesis and structures of triptycene-derived Tr?ger's base molecular clips

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Chinese Chemical Letters 2015年第7期26卷 839-842页

作者： peng-fei li Ying Han Chuan-Feng Chen Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences

A series of triptycene-derived Tr6ger＇s bases with molecular clip shaped structures have been conveniently and efficiently synthesized by one-pot condensation of corresponding amino-substituted triptycenes with paraformaldehyde in the presence of trifluoroacetic acid, and their structures have been characterized by NMR, MALDI-TOF MS spectra, elemental analyses and single-crystal X-ray diffraction. ~ 2015 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

关键词： Triptycene Troger's base Molecular clip Synthesis

Squamous cell carcinoma of the nail bed: A case report

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World Journal of Clinical Cases 2019年第21期7卷 3590-3594页

作者： peng-fei li Ning Zhu Hui Lu Department of Plastic and Aesthetic Center The First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310000Zhejiang ProvinceChina Department of Ophthalmology The First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310000Zhejiang ProvinceChina Department of Orthopedics The First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Squamous cell carcinoma(SCC)of the nail bed is a poorly reported malignant subungual *** it presents with nonspecific symptoms and signs,it is frequently misdiagnosed by dermatologists or surgeons.A delay in diagnosis and/or wrong treatment might increase the possibility of disease ***,new perspectives are needed to assist dermatologists and surgeons with diagnosing and treating *** rare case presented with a 2-year delay in the diagnosis of SCC teaches a valuable *** SUMMARY A 62-year-old female presented with a non-healing subungual growth in the nail bed of the right middle finger for 2 *** lesion was first medicated with iodine by the patient herself without any *** months later,a dermatologist diagnosed the lesion as paronychia and treated it with nail avulsions repeatedly with no obvious alleviation.A lesionectomy confirmed the lesion was *** extended excision of the tumor with amputation of the distal interphalangeal joint was subsequently performed.A biopsy of sentinel lymph nodes was *** to the result of preoperative positron emission tomography-computed tomography scanning,sweeping of axillary lymph nodes was considered dispensable and was *** the 2-year follow-up,the patient showed a quick recovery and no sign of *** Our successful diagnosis and treatment of the case highlights the need for additional attention to long-standing non-healing lesions of the nail bed and the necessity for discreet evaluation and customization of surgical interventions.

关键词： Squamous cell carcinoma Nail bed lesion Customized treatment Malignant subungual tumor Case report

Crystal structure and phase transition of 2-methoxyanilinium perchlorate-18-crown-6

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Chinese Chemical Letters 2014年第5期25卷 723-726页

作者： Wei-Qiang liao Qin-Qin Zhou peng-fei li Yi Zhang Ordered Matter Science Research Center College of Chemistry and Chemical EngineeringSoutheast University

A new phase transition compound,2-methoxyanilinium perchlorate-18-crown-6（1） {（oCH3OC6H4NH3）＋（18-crown-6） ClO4 },has been synthesized and separated as *** scanning calorimetry（DSC） measurements show a pair of sharp peaks at 225 K（heating） and 210 K（cooling）,indicating the phase transition is *** anomalies observed at 225 K（heating）and 210 K（cooling） further confirm the phase *** crystal structures determined at 298 K and123 K are both triclinic in P *** most distinct difference between room-temperature and lowtemperature structures is the order–disorder transition of the host 18-crown-6 molecule,which is the driving force of the phase transition.

关键词： Phase transition Dielectric Crystal structure Host molecule

Heat exposure and hospitalizations for chronic kidney disease in China: a nationwide time series study in 261 major Chinese cities

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Military Medical Research 2024年第4期11卷 469-478页

作者： Fu-lin Wang Wan-Zhou Wang fei-fei Zhang Su-Yuan peng Huai-Yu Wang Rui Chen Jin-Wei Wang peng-fei li Yang Wang Ming-Hui Zhao Chao Yang Lu-Xia Zhang Institute of Medical Technology Peking University Health Science CenterBeijing 100191China National Institute of Health Data Science at Peking University Beijing 100191China Department of Occupational and Environmental Health Sciences School of Public HealthPeking UniversityBeijing 100191China Renal Division Department of MedicinePeking University First HospitalPeking University Institute of NephrologyBeijing 100034China Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases Chinese Academy of Medical SciencesBeijing 100034China Advanced Institute of Information Technology Peking UniversityHangzhou 311215China National Climate Center China Meteorological AdministrationBeijing 100081China Peking-Tsinghua Center for life Sciences Beijing 100034China

Background:Climate change profoundly shapes the population health at the global ***,there was still insufficient and inconsistent evidence for the association between heat exposure and chronic kidney disease(CKD).Methods:In the present study,we studied the association of heat exposure with hospitalizations for cause-specific CKD using a national inpatient database in China during the study period of hot season from 2015 to *** time-series regression models and random-effects Meta-analysis were developed to estimate the city-specific and national averaged associations at a 7 lag-day span,***:A total of 768,129 hospitalizations for CKD was recorded during the study *** results showed that higher temperature was associated with elevated risk of hospitalizations for CKD,especially in sub-tropical *** a 1℃ increase in daily mean temperature,the cumulative relative risks(RR)over lag 0-7 d were 1.008[95% confidence interval(CI)1.003-1.012]for *** attributable fraction of CKD hospitalizations due to high temperatures was 5.50%.Stronger associations were observed among younger patients and those with obstructive *** study also found that exposure to heatwaves was associated with added risk of hospitalizations for CKD compared to non-heatwave days(RR=1.116,95%CI 1.069-1.166)above the effect of daily mean ***:Short-term heat exposure may increase the risk of hospitalization for *** findings provide insights into the health effects of climate change and suggest the necessity of guided protection strategies against the adverse effects of high temperatures.

关键词： Chronic kidney disease Hospitalization Climate change Temperature Time-series study

light weighting opportunities and material choice for commercial vehicle frame structures from a design point of view

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Advances in Manufacturing 2015年第1期3卷 19-26页

作者： Peter Seyfried Ed Juarez Mendes Taiss Alexandre Costa Calijorne fei-peng li Qi-Feng Song Hamburg University of Applied Sciences Hamburg Germany Companhia Brasileira de Metalurgia e Mineracao Villa NovaMGBrazil Caltra Projetos & Consultoria Belo HorizonteMGBrazil Dongfeng Commercial Vehicle Technology Center FAW Technology Center

This paper focuses on an estimation of light weighting opportunities for the frame structure of com- mercial road vehicles. This estimation is based on simpli- fied static load cases which play a predominant role for the dimensioning of a frame structure and therefore these simplifications are not putting the general validity of the conclusions into question. A comparison of different ma- terials under this scenario shows that light metals do not show any weight reduction advantage in comparison to steel while a material-independent topology optimization has more weight reduction potential for the frame structure than a simple change of materials. Considering the con- straints of part complexity which is directly linked with production and assembly cost, the ladder frame structure has become the current state of the art design. Thus the paper also puts a spotlight on basic rules of node design and vertical load induction in order to keep the weight of such a design as low as possible. Practical examples from manufacturers show that the weight of a commercial vehicle could be reduced by 10%, and main parts of the frame structure could be reduced by 30% using high strength steel in combination with innovative production methods like roll forming.

关键词： Ladder frame . light weighting.Commercialvehicle .Node design - High strength steel - Profilesection . Vertical bending .Topology optimization

深埋圆形富水隧道应力与位移的弹塑性解（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2014年第6期15卷 395-404页

作者： peng-fei li Qian FANG Ding-li ZHANG Key Laboratory of Urban Security and Disaster Engineering Ministry of Education Beijing University of Technology Beijing Collaborative Innovation Center for Metropolitan Transportation Key Laboratory for Urban Underground Engineering of the Education Ministry Beijing Jiaotong University

研究目的:推导获得深埋圆形富水隧道应力场与位移场分布的弹塑性解析解。创新要点:基于弹性力学厚壁圆筒受均布压力的拉姆解答和Mohr-Coulomb屈服条件,推导了考虑渗流作用和应力释放时含衬砌深埋隧道的弹塑性解,并采用FLAC3D有限差分程... 详细信息

研究目的:推导获得深埋圆形富水隧道应力场与位移场分布的弹塑性解析解。创新要点:基于弹性力学厚壁圆筒受均布压力的拉姆解答和Mohr-Coulomb屈服条件,推导了考虑渗流作用和应力释放时含衬砌深埋隧道的弹塑性解,并采用FLAC3D有限差分程序验证了其正确性。研究方法:通过理论分析建立考虑渗流作用和应力释放的含衬砌深埋圆形隧道的解析模型(图1),然后推导了基于Mohr-Coulomb屈服准则的隧道围岩与衬砌渗流场、位移场和应力场计算的弹塑性解析公式,并通过数值模拟程序(图2)验证了推导公式的正确性。重要结论:基于前人研究基础,推导获得了深埋富水隧道应力与位移场分布的理论解析解,并通过数值模拟方法验证了其正确性。该解析解一方面可以用于深埋高水头隧道的预设计,如预测隧道周围的水压力、应力场和位移场分布规律,另一方面可用于校核大型复杂数值模型的正确性。

关键词：深埋隧道渗流力平面应变模型应力释放塑性半径

Analytical solutions to ground settlement induced by ground loss and construction loadings during curved shield tunneling

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第4期22卷 296-313页

作者： Shao-hua li Ming-ju ZHANG peng-fei li Key Laboratory of Urban Security and Disaster Engineering of the Ministry of Education Beijing University of TechnologyBeijing 100124China China Railway 15th Bureau Group Co. Ltd.Shanghai 200070China

This paper focuses on the ground settlement induced by the construction of a curved shield *** loss and construction loadings are the two factors causing ground settlement,and two corresponding analytical models were ***,the ground settlement due to ground loss was analyzed based on 3D image ***"integrative gap at shield tail"(IGST)and overcutting gap of a curved tunnel were ***,the ground settlement due to construction loadings was analyzed by modifying Mindlin's *** additional thrust,frictional force,and grouting pressure were ***,a case study and a parameter analysis were ***,the obtained solutions were compared with a classical analytical solution,numerical simulations,and monitored *** proposed model could effectively predict the ground settlement in-duced during curved shield tunneling.

关键词： Curved tunnel Image theory Mindlin's solution Ground loss Ground settlement