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Perfect reconstruction image modulation based on BEMD and quaternionic analytic signals

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Science china(Information sciences) 2011年第12期54卷 2622-2634页

作者： QIAO liHong 1 , NIU KaiFu 2., wang {2. 2.& peng lizhong 2.1 College of Information Science and Engineering, Henan university of Technology, Zhengzhou 450001, china 2.school of mathematical sciences, peking university, Beijing 100871, china 1. College of Information Science and Engineering Henan University of Technology Zhengzhou 450001 China2. School of Mathematical Sciences Peking University Beijing 100871 China

Image modulation represents image by meaningful characters such as image instantaneous amplitude and instantaneous frequency. A perfect reconstruction image modulation method is proposed. In detail, the bidimensional empirical mode decomposition (BEMD) is first improved to adaptively decompose image into monocomponents. Then by the quaternionic analytic method, suitable analytic signals is acquired. A new polar form is further proposed to modulate images, then seven characters are derived including instantaneous amplitude and instantaneous frequencies. We demonstrate the techniques on both synthetic and natural images, depict the needle program of the estimated frequencies and obtain the reconstructions that are the same with the original images. The applications in image segmentation and separation establish the validity of characterizing images of this type as sums of locally narrow band modulated components.

关键词： perfect reconstruction image modulation AM-FM representation BEMD quaternionic analytic signals

Outcomes of endoscopic sclerotherapy for jejunal varices at the site of choledochojejunostomy (with video): Three case reports

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World Journal of Gastroenterology 2024年第14期30卷 2059-2067页

作者： Jun liu peng {2. li-Mei {2. Jing Guo ning Zhong Department of Gastroenterology Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina

BACKGROUND Hemorrhage associated with varices at the site of choledochojejunostomy is an unusual,difficult to treat,and often fatal manifestation of portal *** far,no treatment guidelines have been *** SUMMARY We reported three patients with jejunal varices at the site of choledochojejun-ostomy managed by endoscopic sclerotherapy with lauromacrogol/α-butyl cyanoacrylate injection at our institution between June 2.2. and August *** reviewed all patient records,clinical presentation,endoscopic findings and treatment,outcomes and *** patients who underwent pancre-aticoduodenectomy with a Whipple anastomosis were examined using conven-tional upper gastrointestinal endoscopy for suspected hemorrhage from the afferent jejunal *** with stigmata of recent hemorrhage or active he-morrhage were observed around the choledochojejunostomy site in all three *** injection of lauromacrogol/α-butyl cyanoacrylate was carried out at jejunal varices for all three *** bleeding ceased and patency was observed for 2. and 2.months in two *** one patient with multiorgan failure and internal environment disturbance,rebleeding occurred 1 month after endoscopic sclerotherapy,and despite a second endoscopic sclero-therapy,repeated episodes of bleeding and multiorgan failure resulted in eventual *** We conclude that endoscopic sclerotherapy with lauromacrogol/α-butyl cyanoac-rylate injection can be an easy,effective,safe and low-cost treatment option for jejunal varicose bleeding at the site of choledochojejunostomy.

关键词： Endoscopic sclerotherapy Jejunal varices Choledochojejunostomy Portal vein hypertension Case report

Effects of heat treatment on microstructures and properties of a heterostructured alloy with dissimilar components fabricated by WAAM

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Rare Metals 2024年第9期43卷 4441-4461页

作者： Ming-Cai Pan Jun-Qiang Xu Yong peng ning-ning liang Si Lan Qi Zhou Ke-Hong wang school of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Key Laboratory of Controlled Arc Intelligent Additive Manufacturing Technology Nanjing 210094China

Heat treatment significantly influences homogeneous material microstructures and mechanical properties,which can be improved by an optimal heat treatment ***,heat treatment application to heterogeneous materials presents significant challenges due to compositional and microstructural ***,a laminated heterostructured alloy comprising alternating316L stainless steel(SS)and 18Ni300 maraging steel(MS)layers fabricated using wire and arc additive manufacturing was investigated.A solution treatment was applied at900℃for 0.5 ***,the solution-treated and asfabricated(AF)samples were aged at 500℃for 4 h;these samples were denoted SA and AT,*** AT phase compositions and orientations were similar to those of *** SA 316L SS layer resembled that of AF,but the SA 18Ni300 MS layers exhibited a reduced austenite phase fraction and refined grain size,attributable to solid-state *** the AT sample,aging induced the formation of nanoscale acicularωphase and ellipsoidal Ni_(3)Ti,Fe_(2.Mo,and X precipitates in the 18Ni300 MS ***,the SA precipitates contained acicular Fe Ni_(2.and ellipsoidalω,Ni_(3)Ti,and X precipitates,and their fractions were lower than those in AT ***18Ni300 MS layer microhardness in the heat-treated samples increased due to nanoprecipitation,but the 316L SS layer microhardness resembled that of *** AT and SA ultimate tensile strengths increased to(1360±50)and(1473±41)MPa,respectively,attributable to precipitation *** SA 316L SS layer exhibited a high stress-induced martensite fraction,enhancing the ductility of heated samples.

关键词： Laminated heterostructured alloy Heat treatment Wire and arc additive manufacturing Microstructure Mechanical property

Rational cathode configuration with bilayer membranes to engineer current-collector-free high-areal-sulfur lithium-sulfur batteries

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Nano Research 2024年第6期17卷 5224-5232页

作者： Jianmei Han Hua Zhang peng wang {2. Song Xuguang An Baojuan Xi Shenglin Xiong College of Chemistry and Chemical Engineering Taishan UniversityTai’an 271021China Key Laboratory of the Colloid and Interface Chemistry Ministry of Educationand School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100China school of Mechanical Engineering Chengdu UniversityChengdu 610106China

The application of light-weight current collectors is preferred because of the increased energy density of the *** it in mind,the cathode is designed with self-made paperlike memberane as current collector coupled with another interlayer to enable the high-energy-density lithium-sulfur *** a facile and green step-by-step methodology,the hybrid membrane is finalized successfully,consisting of reduced graphene oxide sheets covering paper-derived carbon(GPC)bearing Fe@Fe2.3 and Fe1−xS@Fe2.3 core-shell nanoparticles(FeFeO/FeSFeO@GPC).The film works as the current collector and interlayer simultaneously considering the porous and conductive *** demonstrated by the electrochemical testing,the FeFeO/FeSFeO@GPC hybrid cell exhibits attractive cycling stability and superior rate *** cell configuration and structural/composition merits of FeFeO/FeSFeO@GPC film facilitate the faster reaction kinetics,conducive to the improvement of capacity *** view of the effective cathode design,the areal sulfur loading is increased to 10.46 mg·cm^(−2.and a reversible capacity of 6.67 mAh·cm^(−2.can be retained after 60 cycles at 0.1 C.

关键词： light-weight self-made current collector core-shell high-areal-sulfur lithium-sulfur batteries

Performance optimization of chalcogenide catalytic materials in lithium-sulfur batteries:Structural and electronic engineering

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Chinese Chemical Letters 2024年第7期35卷 147-166页

作者： Jianmei Han peng wang Hua Zhang {2. Song Xuguang An Baojuan Xi Shenglin Xiong College of Chemistry and Chemical Engineering Taishan UniversityTai'an 271021China Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShandong UniversityJi'nan 250100China school of Mechanical Engineering Chengdu UniversityChengdu 610106China

lithium-sulfur batteries(LSBs)boasting remarkable energy density have garnered significant attention within academic and industrial ***,the progression of LSBs remains constrained by the languid redox kinetics intrinsic to sulfur and the pronounced shuttle effect induced by lithium polysulfides(li PSs),which seriously affecting the energy density,cycling life and rate *** conceptualization and implementation of catalytic materials stand acknowledged as a propitious stratagem for orchestrating kinetic modulation,particularly in excavating the conversion of liPSs and has evolved into a focal point for *** them,chalcogenide catalytic materials(CCMs)have shown satisfactory catalytic effects ascribe to the unique physicochemical properties,and have been extensively developed in recent *** the lack of systematic summary regarding the development of CCMs and corresponding performance optimization strategies,herein,we initiate a comprehensive review regarding the recent progress of CCMs for effective collaborative immobilization and accelerated transformation kinetics of li *** that,the modulation strategies to improve the catalytic activity of CCMs are summarized,including structural engineering(morphology engineering,surface/interface engineering,crystal engineering)and electronic engineering(doping and vacancy,etc.).Finally,the application prospect of CCMs in LSBs is clarified,and some enlightenment is provided for the reasonable design of CCMs serving practical LSBs.

关键词： lithium-sulfur batteries Chalcogenide Catalytic materials lithium polysulfides Structural engineering Electronic engineering

Preparation of three-dimensional nanoporous copper foil with high specific surface area

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Rare Metals 2024年第7期43卷 3430-3437页

作者： ning Song li-Juan {2. Jun-Feng {2. Juan liao Jian Huang peng-Kang Du Yun-Zhi Tang Yu-Hui Tan Xiao-Wei Fan Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry School of Chemistry and Chemical EngineeringJiangxi University of Science and TechnologyGanzhou 341000China

The porous copper foil material has the advantages of ultralight and ultra-thin,and can prevent dangers such as thermal runaway and battery fire,which could be regarded as a prospective material for lithium battery **... 详细信息

关键词： copper porous dimensional

Altered interaction network in the gut microbiota of current cigarette smokers

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Engineering Microbiology 2024年第2期4卷 44-50页

作者： Zhouhai Zhu Meng wang Ying Guan Meng li Qiyuan {2. ning Zheng Wenbin Ma Joint Institute of Tobacco and Health Kunming 650106China State Key Laboratory of Microbial Technology Institute of Microbial TechnologyShandong UniversityQingdao 266237China Department of Neurology Binzhou Medical University HospitalBinzhou 256600China

The association between cigarette smoking and the gut microbiota remains unclear,and there is no agreement on how smoking affects the composition of gut *** this study,the relationship between smoking status and gut microbial composition was investigated by performing 16S rRNA gene amplicon sequencing anal-ysis of stool samples from 80 healthy Chinese *** results showed that smoking did not cause significant changes to the composition and microbial functional pathways of the gut ***,smoking altered the relative abundance of several specific taxa,where Phascolarctobacterium and Fusobacterium increased and Dialister ***,our analysis revealed that smoking introduced more microbial interactions to the interaction network and decreased its ***,this study provides new insights into the association between smoking status and the gut microbiota.

关键词： Cigarette smoking Gut microbiota china Co-occurrence network

Concise Synthesis of Lactococcus garvieae lipoteichoic Acids Through an Additive-Modulated Preactivation Protocol and the Immunological Studies

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CCS Chemistry 2024年第2期6卷 403-414页

作者： Tianlu li Tong li Yue Yang Haoru Zhuang Jianwu Lv {2. Zhou Miaomiao Zhang Fengshan wang Yiqun Geng Richard R.Schmidt peng peng National Glycoengineering Research Center Shandong Key Laboratory of Carbohydrate Chemistry and GlycobiologyNMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate Based MedicineShandong UniversityQingdao 266237 State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050 Department of Chemistry University of KonstanzD-78457 Konstanz

lipoteichoic acids(LTAs)are macroamphiphiles composed of alditol,lipid,phosphate,and carbohydrate *** to their inherent complexity,it is a severe challenge to access LTAs with structural integrity from natural sources for biological or immunological ***,we describe the first total synthesis of Lactococcus garvieae LTA(type II LTA),contai{2. five distinct 1,2.cis gluco/galactopyranosidic linkages,via a novel additive-modulated O-glycosyl trichloroacetimidate preactivation glycosidation *** strategy features(1)high glycosidation yields and excellent 1,2.cis stereoselectivities independent of the donor anomeric configuration,(2.common and inexpensive reagents as promoters and additives,(3)application to standard glycosyl imidate donors without resorting to participating protection,and(4)general application to reactive and less reactive glycosyl ***,via the precise stereocontrolled construction of three galactopyranosidic and two glucopyranosidic bonds on a multigram scale,a series of structurally well-defined LTA molecules were successfully *** evaluation of these type II synthetic LTAs showed a structure–activity relationship in the stimulation of a proinflammatory response.

关键词： 1,2.cis glycosidation stereoselectivity lipoteichoic acid total synthesis additive-modulated trichloroacetimidate glycosidation immune response

A post-modification strategy to precisely construct dual-atom sites for oxygen reduction electrocatalysis

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Journal of Energy Chemistry 2024年第3期90卷 511-517,I0012页

作者： Juan wang Xinyan liu Chang-Xin Zhao Yun-Wei Song Jia-{2. liu Xi-Yao li Chen-Xi Bi Xin Wan Jianglan Shui Hong-Jie peng Bo-Quan li Jia-Qi Huang school of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Institute of Fundamental and Frontier sciences University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina school of Materials Science and Engineering Beihang UniversityBeijing 100191China

Dual-atom catalysts(DACs) afford promising potential for oxygen reduction electrocatalysis due to their high atomic efficiency and high intrinsic ***,precise construction of dual-atom sites remains a *** this work,a post-modification strategy is proposed to precisely fabricate DACs for oxygen reduction ***,a secondary metal precursor is introduced to the primary single-atom sites to introduce direct metal-metal interaction,which ensures the formation of desired atom pair structure during the subsequent pyrolysis process and allows for successful construction of *** as-prepared FeCo-NC DAC exhibits superior oxygen reduction electrocatalytic activity with a half-wave potential of 0,91 V *** hydrogen ***-air batteries equipped with the FeCo-NC DAC demonstrate higher peak power density than those with the Pt/C *** importantly,this post-modification strategy is demonstrated universal to achieve a variety of dual-atom *** work presents an effective synthesis methodology for precise construction of catalytic materials and propels their applications in energy-related devices.

关键词： Dual-atom catalysts Electrocatalysis Oxygen reduction reaction Post-modification Zinc–air batteries