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Characterizations of weighted Besov Spaces with Variable Exponents

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Acta Mathematica Sinica,English Series 2024年第11期40卷 2855-2878页

作者： Sheng Rong wang peng Fei GUO jing shi XU School of Mathematics and Statistics Hainan Normal UniversityHaikou571158P.R.China Center for Applied Mathematics of Guangxi Guangxi Colleges and Universities Key Laboratory of Data Analysis and ComputationSchool of Mathematics and Computing ScienceGuilin University of Electronic TechnologyGuilin541004P.R.China

In this paper,we first give characterizations of weighted Besov spaces with variable exponents via Peetre’s maximal *** we obtain decomposition characterizations of these spaces by atom,molecule and *** an applicatio... 详细信息

关键词： Besov space Muckenhoupt weight variable exponent Peetre’s maximal function atom molecule wavelet pseudo-differential operator

Effect of boron addition on microstructure and mechanical properties of an additively manufactured superalloy

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Journal of Iron and Steel Research International 2023年第3期30卷 601-609页

作者： Rui wang Dao-hong wang peng Zhang zhi-qing Yang jing-jing Liang Jin-guo Li shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026AnhuiChina Jiang Su Feiyue Machine and Pump Group Co. Ltd.Jingjiang 225300JiangsuChina

The effect of boron addition(0.010,0.015,and 0.020 wt.%)on the microstructure and mechanical properties of an additively manufactured superalloy was *** as-built microstructure was investigated by scanning electron microscopy and transmission electron *** results demonstrate that boron precipitates as M_(3)B_(2)boride at the grain *** increase in boron content increases the amount ofγ/γ′eutectic and the size and fraction of M_(3)B_(2)*** creates nanoscale fine borides at grain boundaries,which significantly reinforces grain *** mechanical property analysis indicated that the addition of boron improved the tensile ductility at 760℃and stress rupture properties at 760℃/780 ***,with the excessive addition of boron,the mechanical property was reduced.

关键词： Additive manufacturing Superalloy Boron Grain boundary Stress rupture Tension

Fabrication of Polymersomes with Controllable Morphologies through Dewetting w/o/w Double Emulsion Droplets

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Chinese Journal of Polymer Science 2016年第4期34卷 475-482页

作者： wei-cai wang Kai shi Yan-xiong Pan Chao peng Zi-liang Zhao wei Liu yong-gang Liu 姬相玲 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Aeademy of Sciences Changchun 130022 China

In this work, monodisperse giant polymersomes are fabricated by dewetting of water-in-oil-in-water double emulsion droplets which are assembled by amphiphilic block copolymer molecules in a microfluidic device. The dewetting process can be tuned by solvation between solvent and amphiphilic block copolymer to get polymersomes with controllable morphology. Good solvent （chloroform and toluene） hinders dewetting process of double emulsion droplets and gets acornlike polymersomes or patched polymersomes. On the other hand, poor solvent （hexane） accelerates the dewetting process and achieves complete separation of inner water phase from oil phase to form complete bilayer polymersomes. In addition, twin polymersomes with bilayer membrane structure are formed by this facile method. The formation mechanism for different polymersomes is discussed in detail.

关键词： Polymersomes Double emulsion droplets Dewetting Microfluidic device.

Insights on high temperature friction mechanism of multilayer ta-C films

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Journal of Materials Science & Technology 2022年第2期97卷 29-37页

作者： jing wei peng Guo Hao Li Peiling Ke Aiying wang Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Ningbo Institute of Industrial Technology Ningbo 315201China

In this work,the high temperature friction mechanism of the tetrahedral amorphous carbon(ta-C)film was *** multilayer ta-C film with alternating hard and soft sub-layers exhibited a low friction coefficient of 0.14 at 400℃ before a sudden failure occurred at 4600 *** wear failure was attributed to the gradual consumption of the ta-C film at the contact *** design of a hard or soft top layer effectively regulated the high temperature friction properties of the multilayer *** addition of a hard top layer contributed to a low friction coefficient(0.11)and a minor wear rate(4.0×10^(-7)mm^(3)/(N m)),while a soft top layer deteriorated the lubrication *** was proposed that the passivation of dangling bonds at the sliding interface dominated the low-friction mechanism of the ta-C film at high temperature,while the friction induced graphitization and the formation of sp^(2)-rich carbonaceous transfer layer triggered C-C inter-film bonding,resulting in serious adhesion force and lubrication ***,the multilayer ta-C film with hard top layer obtained excellent friction performance within 500℃,while the high temperature induced oxidation and volatilization of carbon atoms led to the wear failure at 600℃.

关键词： Tetrahedral amorphous carbon Multilayer structure High temperature friction Wear mechanism

Extremely Anisotropic Thermoelectric Properties of SnSe Under Pressure

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Energy & Environmental Materials 2023年第3期6卷 58-65页

作者： wei Cao Ziyu wang Ling Miao jing shi Rui Xiong Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan 430072China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China Suzhou Institute of Wuhan University Suzhou 215123China School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China

SnSe has attracted extensive attention due to its ultralow thermal conductivity and excellent thermoelectric *** this work,pressure-induced thermoelectric properties of Pnma SnSe are investigated via first-principles *** uncover distinct energy isosurfaces topology transition of conduction band by applying *** newly created conduction band valley caused by pressure has a distinct anisotropic shape compared to the old *** pressure can greatly enhance the anisotropy of electronic transport properties of the n-type Pnma ***,the lattice thermal conductivity also exhibits anisotropic behavior under pressure due to a special collaged phonon *** pressure-induced lattice thermal conductivity along the a-axis shows a slower growth trend than that along the b-axis and *** optimal ZT value of the n-type Pnma SnSe along the a-axis can reach 1.64 at room *** results would be helpful for designing the Pnma SnSe-based materials for the potential thermoelectric and valleytronic applications.

关键词： first-principles calculations pressure SnSe thermoelectric materials

Investigation of regulating rheological properties of water-based drilling fluids by ultrasound

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Petroleum Science 2021年第6期18卷 1698-1708页

作者： wei-An Huang jing-Wen wang Ming Lei Gong-Rang Li zhi-Feng Duan zhi-Jun Li shi-Fu Yu School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Sinopec Shengli Petroleum Engineering Co. Ltd.Drilling Technology Research InstituteDongying257017ShandongChina Oil and Gas Technology Research Institute of Changqing Oilfield Branch Xi'an710018ShaanxiChina Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Qingdao266580ShandongChina sPetroChina Daqing Oilfield Co. Ltd.Research Institute of Oil Production EngineeringDaqing163000HeilongjiangChina

Regulating rheological properties of water-based drilling fluids has always been a hot *** paper proposed a new method for regulating rheological properties of water-based drilling fluids by ultrasonic *** experimental results showed that the ultrasound increased the viscosity and yield point of bentonite suspension by reducing the particle size of clay,destroying the network structure between clay particles,increasing the mud yield and the cation exchange capacity of bentonite,and promoting the hydration dispersion of *** change of rheological property showed a memory effect at room temperature and high ***,the ultrasonic energy affected the network structure between clays and polymer chains,thus regulating the rheological properties of the bentonite-polymer *** two types of drilling fluids investigated,the rheology of the poly-sulfonate drilling fluid was regulated by damaging the grid structure between additives and clays by low-power ultrasound and reducing the clay particle size by high-power ultrasound,while the rheology of the deep-water drilling fluid was mainly regulated by disentangling the spatial grid structure between ***,ultrasound showed no effect on the lubricity,inhibition and stability of drilling fluids,which proved the feasibility of ultrasound to regulate rheological properties of water-based drilling fluids.

关键词： Ultrasound Suspension Water-based drilling fluid Rheological property

Mechanical and damping performances of TPMS lattice metamaterials fabricated by laser powder bed fusion

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China Foundry 2024年第4期21卷 327-333页

作者： Yan-peng wei Huai-qian Li jing-jing Han Ying-chun Ma Hao-ran Zhou jing-chang Cheng Jian shi zhi-quan Miao Bo Yu Feng Lin National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China

Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ***,its vibration and noise reduction,and damping properties have not been fully ***,in this study,the TPMS structures with parameterization were designed by the method of surface migration,and the TPMS structures with high forming quality was manufactured by laser powder bed fusion(LPBF).The mechanical properties and energy absorption characteristics of the beam and TPMS structures were studied and compared by quasi-static *** modal shapes of the beam lattice structures and TPMS structures were obtained by the free modal analysis,and the damping properties of two structures were obtained by modal *** the two structures after heat treatment with the same porosity of 70%,the yield strength of the beam lattice structure reaches 40.76 MPa,elastic modulus is 20.38 GPa,the energy absorption value is 32.23 MJ·m^(-3),the damping ratio is 0.52%.The yield strength,elastic modulus,energy absorption value,and damping ratio of the TPMS structure are 50.74 MPa,25.37 GPa,47.34 MJ·m^(-3),and 0.99%,*** results show that TPMS structures exhibit more excellent mechanical properties and energy absorption,better damping performance,and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity.

关键词： lattice metamaterials TPMS energy absorption damping laser powder bed fusion

Obesity rather than Metabolic Syndrome is a Risk Factor for Subclinical Hypothyroidism and Thyroid Autoimmunity

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Biomedical and Environmental Sciences 2021年第10期34卷 819-823页

作者： YAO Jin Yin LIU peng ZHANG wei wang Ke wei LYU Chun peng ZHANG zhi wei CHEN Xiang Lan CHEN Yi wang Xue Song DING yong Xia MA Li Jun wang jing SUN Dian Jun Center for Endemic Disease Control Chinese Center for Disease Control and PreventionHarbin Medical UniversityHarbin 150081HeilongjiangChina Institute of Endemic Disease Control Shandong ProvinceJinan 250000ShandongChina Heze Center for Disease Control and Prevention Heze 274000ShandongChina Jining Center for Disease Control and Prevention Jining 272000ShandongChina

In recent years,the incidences of thyroid diseases have gradually increased,and they may be associated with the development of diagnostic technologies,elevated public health awareness,nuclear radiation,environmental pollution,changes in lifestyle,work stress,excessive iodine intake,and other *** obesity can cause changes to the hypothalamic-pituitary-thyroid axis and deiodinase[1],obesity may be closely related to the high rate of thyroid diseases.

关键词： immunity obesity elevated

Clinicopathological analysis of small intestinal metastasis from extra-abdominal/extra-pelvic malignancy

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World Journal of Gastrointestinal Oncology 2024年第10期16卷 4138-4145页

作者： zhi Zhang jing Liu peng-Fei Yu Hai-Rui Yang Jin-Yang Li zhi-wei Dong wei shi Guo-Li Gu Department of General Surgery Anhui Medical University First Affiliated HospitalHefei 230002Anhui ProvinceChina Department of General Surgery Air Force Clinical CollegeChina Medical UniversityBeijing 100142China Department of General Surgery Air Force Medical CenterAir Force Clinical College of China Medical UniversityBeijing 100142China Department of General Surgery Air Force Medical CenterChinese People’s Liberation ArmyFifth Clinical(Air Force Clinical College)of China Medical UniversityBeijing 100142China Department of General Surgery Beijing Changping HospitalBeijing 102200China Department of General Surgery Air Force Medical CenterBeijing 100142China

BACKGROUND The metastatic tumors in the small intestine secondary to extra-abdominal/extrapelvic malignancy are extremely ***,the small intestine metastases are extremely prone to misdiagnosis and missed diagnosis due to the lack of specific clinical manifestations and examination methods,thus delaying its ***,in order to improve clinical diagnosis and treatment capabilities,it is necessary to summarize its clinical pathological characteristics and *** To summarize the clinicopathological characteristics of patients with small intestinal metastases from extra-abdominal/extra-pelvic malignancy,and to improve the clinical capability of diagnosis and treatment for rare metastatic tumors in the small *** The clinical data of patients with small intestinal metastases from extra-abdominal/extra-pelvic malignancy were retrieved and summarized,who admitted to and treated in the Air Force Medical Center,Chinese People’s Liberation *** descriptive statistics were performed on the general conditions,primary tumors,secondary tumors in the small intestine,diagnosis and treatment processes,and *** Totally 11 patients(9 males and 2 females)were enrolled in this study,including 8 cases(72.3%)of primary lung cancer,1 case(9.1%)of malignant lymphoma of the thyroid,1 case(9.1%)of cutaneous malignant melanoma,and 1 case(9.1%)of testicular *** median age at the diagnosis of primary tumors was 57.9 years old,the median age at the diagnosis of metastatic tumors in the small intestine was 58.81 years old,and the average duration from initial diagnosis of primary tumors to definite diagnosis of small intestinal metastases was 9 months(0-36 months).Moreover,small intestinal metastases was identified at the diagnosis of primary tumors in 4 *** small intestinal metastases were distributed in the jejunum and ileum,with such clinical manifestations as hematochezia(5,45.4%)and abdominal pain,vomiting and other obstr

关键词： Small intestinal Metastases Clinicopathological features Prognostic analysis Malignancy