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Gradient structured Copper by Rotationally Accelerated shot Peening

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Journal of Materials science & Technology 2017年第7期33卷 758-761页

作者： X.Wang Y.s.Li Q.z.ang Y.H.zhao Y.T.zhu Nano structural Materials Center School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China school of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China Department of Materials science and Engineering North Carolina State University Raleigh NC 27695 USA

A new technology-rotationally accelerated shot peening（RAsP）, was developed to prepare gradient structured materials. By using centrifugal acceleration principle and large steel balls, the RAsP technology can produce much higher impact energy compared to conventional shot peening. As a proof-of-concept demonstration, the RAsP was utilized to refine the surface layer in pure copper（Cu） with an average grain size of 85 nm. The grain size increases largely from surface downwards the bulk, forming an800 ？m thick gradient-structured surface layer and consequently a micro-hardness gradient. The difference between the RAsP technology and other established techniques in preparing gradient structured materials is discussed. The RAsP technology exhibits a promoting future for large-scale manufacturing of gradient materials.

关键词： Microstructure Rotationally accelerated shot peening Gradient structure Hardness Copper

High sensitivity dual polarization four channels surface plasmon resonance refractive index sensor with wide detection range and high linearity based on photonic crystal fiber

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Optoelectronics Letters 2025年

作者： CUI Nan PAN Honggang zHANG Ailing zhao zihong CHEN zhipan zHANG Bo Tianjin Key Laboratory of Film Electronic and Communication Devices， Engineering Research Center of Optoelectronic Devices and Communication Technology， Ministry of Education， school of Integrated Circuit science and Engineering， Tianjin University of Technology

In this paper， we propose and numerically characterize the optical characteristics of a high sensitivity dual polarization four channels surface plasmon resonance refractive index sensor with wide detection range and high linearity based on photonic crystal fiber （PCF）. Four light transmission channels are constructed by using big air holes. The small rectangular air hole in the center of the fiber core is used to add asymmetry. We use gold plasma material to achieve better sensing performance. A thin film of TiO2is placed on the PCF surface， which assists gold in the adhesion on PCF. The maximum wavelength sensitivity of the sensor can reach 20000 nm/RIU in both x and y polarization modes. While the maximum wavelength resolution of the sensor is 5×10-6RIU. The average wavelength sensitivity reached 15900nm/RIU and 15800nm/RIU in x and y polarization mode. The sensor features R2=0.9969 / R2=0.9966 high linear performance in x and y polarization mode and the maximum FOM values 509.13 RIU-1/ 489.63 RIU-1in x and y polarization mode. Besides the sensor’s detection range is 1.26-1.36， which is a wide refractive index detection range. The sensor has a wide range of applications in biomedical and other fields.

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技术鹰派、国家安全与美国对华战略竞争

国际安全研究 2025年第1期43卷 115-132,158,159页

作者：赵明昊复旦大学美国研究中心复旦大学一带一路及全球治理研究院上海220433

在新一轮科技革命和地缘政治对抗相互叠加的背景下,技术因素对国家间关系尤其是大国关系的塑造作用越发突出,科技界与国家安全战略之间的联系日益紧密。近年来,美国不断强化对华“科技冷战”,与美国在经济、军事、意识形态、全球治理等... 详细信息

在新一轮科技革命和地缘政治对抗相互叠加的背景下,技术因素对国家间关系尤其是大国关系的塑造作用越发突出,科技界与国家安全战略之间的联系日益紧密。近年来,美国不断强化对华“科技冷战”,与美国在经济、军事、意识形态、全球治理等方面的对华施压相互关联。美国科技企业、风险投资机构等社会性力量和美国国家安全部门之间的沟通协作日益密切,涵盖商界、政界和学界精英的技术鹰派势力逐步成形。技术鹰派认为,美国须牢固捍卫自身技术领导地位,推进对华技术“脱钩”,甚至设法令中国的技术水平倒退,进而以强大的美国技术实力实现对华“竞而胜之”的目标。美国政府着眼对华战略竞争,加快推动构建国家安全创新网络,国防部、国务院、中央情报局等机构与高科技企业的合作更趋深化,美国创新生态的国家安全导向更为突出。加大对华科技竞争已经成为美国共和党和民主党的共识。考虑到美国科技界精英对特朗普的支持,以及副总统万斯、特朗普家族等与硅谷之间错综复杂的社会关系网络,特朗普第二任期的对华科技施压力度或将增强,技术鹰派对中美关系的影响力将更为突出。

关键词：技术鹰派国家安全中美关系技术—安全复合体国家创新生态

Deformation behaviors of as-built and hot isostatically pressed Ti-6Al-4V alloys fabricated via electron beam rapid manufacturing

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Journal of Materials science & Technology 2019年第11期35卷 2552-2558页

作者： z.Liu z.B.zhao J.R.Liu L.Wang s.X.zhu G.Yang s.L Gong Q.J.Wang R.Yang institute of metal research chinese academy of sciencesshenyang110016china school of materials science and engineering university of science and technology of chinahefei230000china avic manufacturing technology institute beijing100024china

The deformation behavior of as-built and hot isostatically pressed(HIP)Ti-6Al-4V alloys fabricated using electron beam rapid manufacturing(EBRM)were investigated in this *** deformation characteristics were characterized using a laser scanning confocal microscope and electron back-scattered diffraction(EBsD).In the as-built sample,prismatic slip was the main mode of deformation,as well as a small amount of basal slip and *** planar slip lines with large length scales were observed across severalα*** hot isostatical pressing,prismatic and basal slip were the main mode of deformation,accompanied by abundant cross-slip and multiple slip,and most of the slip lines were blocked within an a *** differences in deformation behavior were associated with the coarsening of a laths and the more retained p phase after HIP compared to the as-built *** cross-slip and multiple slip can lead to superior elongation-to-failure and a greater strain hardening effect in the HIP alloy compared to the as-built sample.

关键词： Electron beam rapid manufacturing Ti-6Al-4V Hot isostatic pressure Mechanical properties slip behavior

surface modification of tungsten oxide by oxygen vacancies for hydrogen adsorption

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Journal of Materials science & Technology 2022年第22期117卷 23-35页

作者： Q.zhang F.W.Tang z.zhao z.R.Nie X.Y.song Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing the adsorption process of hydrogen on surface of tungsten oxide was proposed based on the first-principle calculations. Multiple factors such as type of active surface, adsorption site and distribution of oxygen vacancies were considered to evaluate the hydrogen adsorption capability of tungsten oxide. The adsorption Gibbs free energies, electronic structures and bonding characteristics under various conditions were examined to reveal the influence of oxygen vacancies on the surface. It is found that the capability of hydrogen adsorption of tungsten oxide can be significantly enhanced by adjusting the oxygen vacancy on the outermost layer of certain active surfaces. The modeling predicts that the surface structure stability and gas adsorption ability of tungsten oxide can be simultaneously improved through the formation of W–H bonds. The proposed strategy for moderating surface provides a new approach to obtain excellent gas-sensitive metal oxide materials.

关键词： Metal oxide Gas-sensitive material surface adsorption Oxygen vacancy First-principles calculation

Coherent nonlinear structures in dense electron positron plasma

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Chinese Physics B 2013年第2期22卷 335-340页

作者： s.A.Khan z.Wazir National Centre for Physics Quaid-i-Azam University CampusIslamabad 45320Pakistan Department of Physics Riphah International UniversityIslamabadPakistan

It is shown that rarefactive-type double layer structures exist in ultradense electron-positron *** this purpose,an extended Korteweg de Vries equation is derived and solved analytically in the low amplitude limit by employing the appropriate fluid equations.A strong influence of quantum degeneracy pressure of electrons and positrons,quantum diffraction effects and concentration of background positive ions on double layer is *** is also pointed out that the amplitude and steepness of the double layer increases with an increase in ion concentration or ion charge *** results are examined numerically for some interesting cases of dense plasmas with illustrations.

关键词： degenerate plasma nonlinear structures double layers

Mesoporous Carbon-Tin Nanocomposites as Anode Materials for Li-ion Battery

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Journal of Materials science & Technology 2008年第4期24卷 657-660页

作者： z. W.zhao z.P.Guo P. Yao H.K.Liu Institute for superconducting and Electronic Materials University of Wollongong NSW 2522 Australia ARC Centre of Excellence for Electromaterials science University of Wollongong NSW 2522 Australia Centre for Analysis and Measurement Tianjin University Tianjin 300072 China

A new mesoporous carbon-tin （MC-sn） nanocomposite has been successfully prepared via a two-step method. From the transmission electron microscopy （TEM） observations, the tin nanoparticles were decorated on the as-prepared mesoporous carbons. The mesoprous structure of the carbon can effectively buffer the volume changes during the Li-sn alloying and de-alloying cycles. The as-prepared MC/sn nanocomposite electrodes exhibited extremely good cycling stability, with the specific capacity of sn in the composite electrode calculated to be 959.7 mAh-g-1, which amounts to an impressive 90.9% of the theoretical value （990 mAh-g-1）. The reversible capacity after 200 cycles is 96.1% of the first cycle reversible capacity, i.e., the capacity fade rate is only 0.0195% per cycle, which is even better than that of commercial graphite-based anodes.

关键词： Mesoporous Carbon Tin Nanocomposites Lithium ion battery

Fecal microbiota transplantation in allergic diseases

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World Journal of Methodology 2025年第2期15卷 83-91页

作者： Ece TüsüzÖnata ÖnerÖzdemir Division of Pediatric Allergy and Immunology Medical FacultySakarya UniversityAdapazarı54100SakaryaTürkiye

Microorganisms such as bacteria,fungi,viruses,parasites living in the human intestine constitute the human intestinal *** refers to composi-tional and quantitative changes that negatively affect healthy gut *** recent years,with the demonstration that many diseases are associated with dysbiosis,treatment strategies targeting the correction of dysbiosis in the treat-ment of these diseases have begun to be *** microbiota trans-plantation(FMT)is the process of transferring faeces from a healthy donor to another recipient in order to restore the gut microbiota and provide a therapeutic *** studies have gained popularity after probiotic,prebiotic,symbiotic studies in the treatment of dysbiosis and related *** has emerged as a potential new therapy in the treatment of allergic diseases as it is associated with the maintenance of intestinal microbiota and immunological balance(T helper 1/T helper 2 cells)and thus suppression of allergic *** this article,the definition,application,safety and use of FMT in allergic diseases will be discussed with current data.

关键词： Microbiota Dysbiosis Faecal microbiota transplantation Allergic diseases

Biomimetic amelioration of zirconium nanoparticles on a rigid substrate over viscous slime--a physiological approach

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Applied Mathematics and Mechanics(English Edition) 2023年第9期44卷 1563-1576页

作者： s.I.ABDELsALAM A.z.zAHER Instituto de Ciencias MatemHu DINGticas ICMAT Madrid 28049Spain Basic science Faculty of EngineeringThe British University in EgyptAl-Shorouk CityCairo 11837Egypt Basic science Department Faculty of EngineeringShubra-Benha UniversityCairo 11884Egypt

In this article,an investigation is conducted to study the precise role of zirconium nanoparticles that exist in a slime-like fluid subject to specific *** gliding is a technique of mobility used by bacteria that lack motility components,bacteria travel on their own strength in gliding locomotion by secreting a layer of slime on the substrate.A model of an undulating sheet over a layer of slime of a Rabinowitsch fluid is investigated as a potential model of bacteria’s gliding *** the aid of long wavelength approximation,the equations governing the circulation of slime underneath the cells are established and analytically *** effects of pseudoplasticity,dilatation and non-Newtonian parameter on the behavior of zirconium concentration,speed of microorganism(bacteria),streamline patterns,and pressure rise for non-Newtonian and Newtonian fluids are *** power required for propulsion is also *** interpretation for the pertinent variables has been graphically discussed against the parameters under *** is found that with the increase in the concentration of zirconium nanoparticles,the bacterial flow is accelerated and attains its maximum near the rigid substrate wall while an opposite behavior is noticed in the rest region.

关键词： zirconium nanoparticle gliding bacterium Grashof heat transfer glider's speed Rabinowitsch fluid