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Fracture Toughness Properties of Three Different Biomaterials Measured by Nanoindentation

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Journal of Bionic Engineering 2007年第1期4卷 11-17页

作者： ji-yu sun jin Tong Key Laboratory of Terrain-Machine Bionics Engineering （Ministry of Education China） Jilin University （Nanling Campus） Changchun 130022 P. R. China

The fracture toughness of hard biomaterials, such as nacre, bovine hoof wall and beetle cuticle, is associated with fibrous or lamellar structures that deflect or stop growing cracks. Their hardness and reduced modulus were measured by using a nanoindenter in this paper. Micro/nanoscale cracks were generated by nanoindentation using a Berkovich tip. Nanoindentation of nacre and bovine hoof wall resulted in pile-up around the indent. it was found that the fracture toughness （Kc） of bovine hoof wall is the maximum, the second is nacre, and the elytra cuticle of dung beetle is the least one.

关键词： biomimetics bionics biomaterials nanoindentation laminated structure fracture toughness

Carrier-assisted differential detection

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Light(Science & Applications) 2020年第1期9卷 1835-1843页

作者： William Shieh chuanbowen sun Honglin ji Department of Electrical and Electronic Engineering The University of MelbourneParkville VIC3010Australia

To overcome power fading induced by chromatic dispersion in optical fiber communications,optical field recovery is a promising solution for direct detection short-reach applications,such as fast-evolving data center interconnects(DCis).To date,various direct detection schemes capable of optical field recovery have been proposed,including Kramers−Kronig(KK)and signal−signal beat interference(SSBi)iterative cancellation(iC)***,they are all restricted to the single sideband(SSB)modulation format,thus conspicuously losing half of the electrical spectral efficiency(SE)compared with double sideband(DSB)***,SSB suffers from the noise folding issue,requiring a precise optical filter that complicates the receiver *** such.it is highly desirable to investigate the field recovery of DSB signals via direct *** this paper,for the first time,we propose a novel receiver scheme called carrier-assisted differential detection(CADD)to realize optical field recovery of complex-valued DSB signals via direct ***,CADD doubles the electrical SE compared with the KK and SSBi iC receivers by adopting DSB modulation without sacrificing receiver ***,by using direct detection without needing a precise receiver optical filter,CADD can employ cost-effective uncooled lasers as opposed to expensive temperature-controlled lasers in coherent *** proposed receiver architecture opens a new class of direct detection schemes that are suitable for photonic integration analogous to homodyne receivers in coherent detection.

关键词： receiver precise coherent

Nusselt number correlation for turbulent heat transfer of helium-xenon gas mixtures

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Nuclear Science and Tech.iques 2021年第11期32卷 119-133页

作者： Biao Zhou Yu ji Jun sun Yu-Liang sun institute of Nuclear and New Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China

A gas-cooled nuclear reactor combined with a Brayton cycle shows promise as a technology for highpower space nuclear power ***,a helium-xenon gas mixture with a molecular weight of14.5-40.0 g/mol is adopted as the working fluid to reduce the mass and volume of the *** Prandtl number for helium-xenon mixtures with this recommended mixing ratio may be as low as *** the convective heat transfer is closely related to the Prandtl number,different heat transfer correlations are often needed for fluids with various Prandtl *** studies have established heat transfer correlations for fluids with medium-high Prandtl numbers(such as air and water)and extremely lowPrandtl fluids(such as liquid metals);however,these correlations cannot be directly recommended for such helium-xenon mixtures without *** study initially assessed the applicability of existing Nusselt number correlations,finding that the selected correlations are unsuitable for helium-xenon *** establish a more general heat transfer correlation,a theoretical derivation was conducted using the turbulent boundary layer *** simulations of turbulent heat transfer for helium-xenon mixtures were carried out using Ansys *** on simulated results,the parameters in the derived heat transfer correlation are *** is found that calculations using the new correlation were in good agreement with the experimental data,verifying its applicability to the turbulent heat transfer for helium-xenon *** effect of variable gas properties on turbulent heat transfer was also analyzed,and a modified heat transfer correlation with the temperature ratio was *** on the working conditions adopted in this study,the numerical error of the property-variable heat transfer correlation was almost within 10%.

关键词： Gas-cooled nuclear reactor Space nuclear power Helium–xenon mixtures Convective heat transfer Nusselt number

Moments of L-Functions Attached to the Twist of Modular Form by Dirichlet characters

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chinese Annals of Mathematics,Series B 2015年第2期36卷 237-252页

作者： Guanghua ji Haiwei sun School of Mathematics Shandong University School of Mathematics and Statistics Shandong University

Let f（z） be a holomorphic cusp form of weight κ with respect to the full modular group SL2（Z）. Let L（s, f） be the automorphic L-function associated with f（z） and χ be a Dirichlet character modulo q. in this paper, the authors prove that unconditionally for k =1/n with n ∈ N,Mk（q,f）=∑χ（mod q）χ≠χ0｜L（1/2,f χ）｜^2k〈〈 kФ（q）（log q）^k^2, and the result also holds for any real number 0 〈 k 〈 1 under the GRH for L（s, f χ）.The authors also prove that under the GRH for L（s, f χ）,for any real number k 〉 0 and any large prime q.

关键词： Moments Automorphic L-functions Convexity theorem

Dilation and breakage dissipation of granular soils subjected to monotonic loading

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Acta Mechanica Sinica 2016年第6期32卷 1065-1074页

作者： Yifei sun Yang Xiao Hua ji Faculty of Engineering and information Sciences University of Wollongong School of Civil and Transportation Engineering Hohai University College of Civil Engineering Chongqing University

Dilation and breakage energy dissipation of four different granular soils are investigated by using an energy balance equation. Due to particle breakage, the dilation curve does not necessarily pass through the origin of coordinates. Breakage energy dissipation is found to increase significantly at the initial loading stage and then gradually become stabilised. The incremental dissipation ratio between breakage energy and plastic work exhibits almost independence of the confining pressure. Accordingly, a plastic flow rule considering the effect of particle breakage is suggested. The critical state friction angle is found to be a combination of the basic friction between particles and the friction contributed by particle breakage.

关键词： Dilation Particle breakage Granular soil Energy dissipation

Nickel-carbonate nanowire array： An efficient and durable electrocatalyst for water oxidation under nearly neutral conditions

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Frontiers of chemical Science and Engineering 2018年第3期12卷 467-472页

作者： Yuyao ji Min Ma Xuqiang ji Xiaoli Xiong Xuping sun College of chemistry and Materials Science Sichuan Normal University Chengdu 610068 China College of chemistry Sichuan University Chengdu 610064 China Key Lab of Process Analysis and Cont ol of Sichuan Universities Yibin University Yibin 644000 China

it is highly attractive but still remains a great challenge to develop an efficient electrocatalyst for oxygen evolution reaction under nearly neutral conditions. in this work, we report the transformation of Ni3S2 nanowire array on nickel foam into the amorphous nickel carbonate nanowire array on nickel foam （NiCO3/NF）. The resulting NiCO3/NF shows high electrocatalytic activity towards water oxidation and affords current density of 50 mA. cm-2 at overpotential of 395 mV in 1.0 mol·L^-1 KHCO3. Moreover, this NiCO3/NF is also durable with a long-term electrochemical durability of 60 h. This catalyst electrode achieves a high turnover frequency of 0.21 mol O2·s^-1 at the overpotential of 500 mV.

关键词： water oxidation NiCO3/NF nearly neutral conditions superior activity electocatalyst

Strict Stability of impulsive Differential Equations

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Acta Mathematica Sinica,English Series 2006年第3期22卷 813-818页

作者： Yu ZHANG ji Tao sun Department of Applied Mathematics Tongji University

in this paper, we will extend the strict stability to impulsive differential equations. By using Lyapunov functions, we will get some criteria for the strict stability of impulsive differential equations, and we can see that impulses do contribute to the system＇s strict stability behavior. An example is also given in this paper to illustrate the efficiency of the obtained results.

关键词： impulsive differential equation Strict stability Lyapunov function

innovative dual-mode device integrating capacitive desalination and solar vapor generation for high-efficiency seawater desalination

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Journal of Energy chemistry 2025年第1期 171-179页

作者： jiacheng Wang Zhaoyu chen Ruduan Yuan jiaxin Luo Ben Zhang Keju ji Meng Li Juanxiu Xiao Kuan sun National innovation Center for industry-Education integration of Energy Storage Technology MOE Key Laboratory of Low-grade Energy Utilization Technologies and SystemsCollege of Energy & Power Engineering Chongqing University Xuefeng Mountain Energy Equipment Safety National Observation and Research Station CQU-NUS Renewable Energy Materials & Devices Joint Laboratory Chongqing University Southwest Technology and Engineering Research.institute jiangsu Provincial Key Laboratory of Bionic Functional Materials College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics 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

Solar-driven interface evaporation with high solar-to-steam conversion efficiency has shown great potential in seawater ***,due to the influence of latent heat and condensation efficiency,the water yield from solar-driven interface evaporation remains insufficient,posing a significant challenge that requires *** this work,we designed a dual-mode high-flux seawater desalination device that combines solar-driven interface evaporation and capacitive *** utilizing coupled desalination materials exhibiting both photothermal conversion and capacitance activity,the device demonstrated photothermal evaporation rates of 1.41 and 0.97 kg m-2h-1for condensate water yield under one-sun ***,the device exhibited a salt adsorption capacity of up to48 mg g-1and a salt adsorption rate of 2.1 mg *** addition,the salt adsorption capacity increased by approximately 32% under one-sun ***,photo-enhanced capacitive desalination performance was explored through numerical simulations and theoretical *** calculations and characterizations confirmed that the defect energy levels formed by the introduction of sulfur vacancies can effectively widen the light absorption range,improve photothermal conversion performance,and stimulate more photoelectrons to participate in capacitive ***,the electron distribution state of molybdenum disulfide with sulfur vacancies and surface defect sites contributes to ion/electron transport at the solid-liquid *** work provides a novel pathway for integrating solar vapor generation with other low-energy desalination technologies.

关键词：

interaction　of　Polyelectrolyte　with　Fluorocarbon　Surfactant　in　Aqueous　Solution

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chinese chemical Letters 1996年第10期7卷 951-953页

作者： Wang, YZ ji, HF Tung, ch Yue, GC ACAD SiNiCA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA jiLiN UNiV DEPT ENVIRONM SCICHANGCHUN 130023PEOPLES R CHINA

The variation of the i1/i3 ratio of the fluorescence of pyrene in polystyrene-based quaternary ammonium salt (PA) and sodium carboxymethylamylose (NaCMA) aqueous solutions was measured as a function of sodium perfluorooctanoate (SPFO) concentration. Association of the anionic fluorocarbon surfactant with cationic polyelectrolyte (PA) to form mixed micelles occurred at the surfactant concentrations far below its normal critical concentration, while no interaction between SPFO and anionic polyelectrolyte (NaCMA) was detected. The driving force for the formation of mixed micelles of *** PA is electrostatic interactions.

关键词： Aqueous Surfactant Fluorocarbon Polyelectrolyte interaction