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Dynamic Impact of High-Density Aluminum Foam

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Acta Mechanica Solida Sinica 2022年第2期35卷 198-214页

作者： Q.Peng J.xie H.S.Ma X.Ling X.Liu y.G.Wei LNM Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China School of Engineering and Technology China University of GeosciencesBeijing 100083China College of Engineering Peking UniversityBeijing 100871China

High-density aluminum foam can provide higher stiffness and absorb more energy during the impact Obtaining the constitutive law of such foam requires tri-axial tests with very high pressure,where difficulty may arise because the hydrostatic pressure can reach more than 30 *** this paper,instead of using tri-axial tests,we proposed three easier tests-tension,compression and shear to obtain the parameters of constitutive model(the Deshpande-Fleck model).To verify the constitutive model both statically and dynamically,we carried out addi-tional triaxial tests and direct impact tests,*** on the derived model,we performed finite element simulation to study the impact response of the present *** dimensional analysis,we proposed an empirical equation for a non-dimensional impact time the impact time divided by the time required for plastic wave travelling from the impact surface to the bottom surface,to det ermine the deformation charac teristic of the aluminum foam after *** the case with t_(d)≤1,the deformation tends to exhibit a shock-type characteristic,while for the case with t_(d)>5,the deformation tends to exhibit an upsetting-type characteristic.

关键词： High density aluminum Foam Deshpande-Fleck model Finite element method Impact analysis Plastic wave

Hayward Quasilocal Energy of Tori

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Chinese Annals of Mathematics,Series B 2022年第5期43卷 773-784页

作者： Xiaokai HE Naqing xie School of Mathematics and Statistics Hunan First Normal UniversityChangsha 410205China School of Mathematical Sciences Fudan UniversityShanghai 200433China

In this paper, the authors show that one cannot dream of the positivity of the Hayward energy in the general situation. They consider a scenario of a spherically symmetric constant density star matched to the Schwarzschild solution, representing momentarily static initial data. It is proved that any topological tori within the star, distorted or not,have strictly positive Hayward energy. Surprisingly we find analytic examples of ‘thin’ tori with negative Hayward energy in the outer neighborhood of the Schwarzschild *** tori are swept out by rotating the standard round circles in the static coordinates but they are distorted in the isotropic coordinates. Numerical results also indicate that there exist horizontally dragged tori with strictly negative Hayward energy in the region between the boundary of the star and the Schwarzschild horizon.

关键词： Quasilocal energy Positivity Toroidal topology

Second Main Theorem for Meromorphic Maps into Algebraic Varieties Intersecting Moving Hypersurfaces Targets

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Chinese Annals of Mathematics,Series B 2021年第5期42卷 753-776页

作者： Libing xie Tingbin CAO Department of Mathematics Nanchang UniversityNanchang 330031China Department of Mathematics Xinyu UniversityXinyu 338004JiangxiChina

Since the great work on holomorphic curves into algebraic varieties intersecting hypersurfaces in general position established by Ru in 2009, recently there has been some developments on the second main theorem into algebraic varieties intersecting moving hypersurfaces targets. The main purpose of this paper is to give some interesting improvements of Ru’s second main theorem for moving hypersurfaces targets located in subgeneral position with index.

关键词： Algebraic varieties Holomorphic curves Nevanlinna theory Moving hypersurfaces

Microstructure and Mechanical Properties of X80 Pipeline Steel Joints by Friction Stir Welding Under Various Cooling Conditions

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Acta Metallurgica Sinica(English Letters) 2020年第1期33卷 88-102页

作者： G.M.xie R.H.Duan P.Xue Z.y.Ma H.L.Liu Z.A.Luo State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Sheny.ng National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

X80 pipeline steel plates were friction stir welded(FSW)under air,water,liquid CO2+water,and liquid CO2 cooling conditions,producing defect-free *** microstructural evolution and mechanical properties of these FSW joints were *** granular bainite was observed in the nugget zone(NZ)under air cooling,and lath bainite and lath martensite increased signifi cantly as the cooling medium temperature *** particular,under the liquid CO2 cooling condition,a dual phase structure of lath martensite and fi ne ferrite appeared in the *** to the case under air cooling,a strong shear texture was identifi ed in the NZs under other rapid cooling conditions,because the partial deformation at elevated temperature was retained through higher cooling *** liquid CO2 cooling,the highest transverse tensile strength and elongation of the joint reached 92%and 82%of those of the basal metal(BM),respectively,due to the weak tempering softening.A maximum impact energy of up to 93%of that of the BM was obtained in the NZ under liquid CO2 cooling,which was attributed to the operation of the dual phase of lath martensite and fi ne ferrite.

关键词： Friction stir welding Pipeline steel Microstructure Mechanical properties Cooling

Multibeam Raman amplification of a finite-duration seed in a short distance

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Chinese Physics B 2021年第10期30卷 428-435页

作者： y G Chen y Chen S X xie N Peng J Q yu C Z Xiao Key Laboratory for Micro-/Nano-Optoelectronic Devices of Ministry of Education School of Physics and ElectronicsHunan UniversityChangsha 410082China Collaborative Innovation Center of IFSA(CICIFSA) Shanghai Jiao Tong UniversityShanghai 200240China

A new scheme of multibeam Raman amplification(MRA)is proposed in virtue of the collective mode by sharing a common scattered *** laser beams can provide a higher growth rate,but the overlapping region limits the amplification *** suggest to use a finite-duration seed to facilitate MRA in a short *** two-dimensional particle-in-cell simulations,we find that two-beam Raman amplification has a much higher growth rate than that of singlebeam *** growth rate depends on the initial seed amplitude,electron temperature,and seed *** empirical criterion,γ0τc=1,whereγ0 is the theoretical growth rate of MRA,is used to choose a proper duration for a higher growth *** a total amplification length of 320µm,the two-beam Raman amplification shows nonlinear features of pulse compression and a bow-shape wave front,indicating that the amplification has finally entered the self-similar regime.

关键词： multibeam Raman amplification growth rate finite-duration

The mechanical behavior of nanoscale metallic multilayers:A survey

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Acta Mechanica Sinica 2015年第3期31卷 319-337页

作者： Q.Zhou J.y.xie F.Wang P.Huang K.W.Xu T.J.Lu State-Key Laboratory for Mechanical Behavior of Material Xi’an Jiaotong University State-Key Laboratory for Mechanical Structure Strength and Vibration Xi’an Jiaotong University

The mechanical behavior of nanoscale metallic multilayers （NMMs） has attracted much attention from both scientific and practical views. Compared with their monolithic counterparts, the large number of interfaces existing in the NMMs dictates the unique behavior of this special class of structural composite materials. While there have been a number of reviews on the mechanical mechanism of micro- laminates, the rapid development of nanotechnology brought a pressing need for an overview focusing exclusively on a property-based definition of the NMMs, especially their size- dependent microstructure and mechanical performance. This article attempts to provide a comprehensive and up-to-date review on the microstructure, mechanical property and plas- tic deformation physics of NMMs. We hope this review could accomplish two purposes：（1） introducing the basic concepts of scaling and dimensional analysis to scientists and engi- neers working on NMM systems, and （2） providing a better understanding of interface behavior and the exceptional qual- ities the interfaces in NMMs display at atomic scale.

关键词： Multilayer Interface Microstructure Mechanical behavior

Effects of Aromatherapy on Physical and Mental Health of Cancer Patients Undergoing Radiotherapy and/or Chemotherapy: A Meta-Analysis

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Chinese Journal of Integrative Medicine 2024年第5期30卷 449-457页

作者： xie Shuang-ran MA Liang XU Xin-yu ZHOU Shu xie Hui-miao xie Chang-sheng The First Clinical Medical College Zhejiang Chinese Medical UniversityHangzhou 310053China Department of Medical Oncology Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical UniversityHangzhou 310007China Department of Dermatology the Third Xiangya HospitalCentral South UniversityChangsha 410013China Department of Famous Chinese Medicine Clinic the Second Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310005China Department of Medical Oncology the First Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310006China

Backgroup:Currently,aromatherapy is being increasingly utilized in clinical practice,particularly in managing the side effects associated with radiotherapy and ***,it remains to be established whether aromatherapy can effectively alleviate these ***:To investigate the effects of aromatherapy on the physical and mental health of patients with cancer undergoing radiotherapy and ***:Seven databases were researched from inception until September 29,2023,including PubMed,Scopus,and Web of Science,Chinese National Knowledge Infrastructure,Wanfang database,China Biology Medicine disc and VIP Chinese Medical Journal *** Manager version 5.3 was utilized for data *** Cochrane Risk of Bias tool RoB2 was employed to evaluate the quality of the literature included in the *** quality rating was assessed using the Grading of Recommendations Assessment,Development,and Evaluation(GRADE) approach through the GRADEpro GDT online ***:Nineteen studies involving 1,541 patients were *** can alleviate nausea [relative risk(RR)=0.64,95% confidence interval(CI):0.53 to 0.78,Png(RR=0.54,95% CI:0.42 to 0.69,Py of life(SMD=0.50,95% CI:0.22 to 0.79,Py and chemotherapy,but it may not have a significant effect on *** risk of bias was high in the included studies using the Cochrane Risk of Bias tool RoB2,and no studies were considered to be of high grade according to the GRADE ***:Aromatherapy is an efficacious,safe a

关键词： aromatherapy cancer chemoradiotherapy physical psychological

SyNTHESIS,HELICITy,AND BIOLOGICAL PROPERTIES OF MONOSACCHARIDE-CONTAINIngPOLy(PHENyLACETyLENE)S

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Chinese Journal of Polymer Science 2007年第2期25卷 119-122页

作者： Jacky W. y. Lam Kevin K. L. Cheuk Bing-shi Li y.ng xie Ben-zhong Tang Department of Chemistry The Hong Kong University of Science ＆ Technology Clear Water Bay Kowloon Hong Kong China Department of Biology The Hong Kong University of Science ＆ Technology Clear Water Bay Kowloon Hong Kong China Department of Polymer Science ＆ Engineering Zhejiang University Hangzhou 310027 China

Poly（phenylacetylene）s beating monosaccharide pendant groups are synthesized in high yields by [Rh（nbd）Cl]2 catalyst. The polymers have high molecular weights and give satisfactory spectroscopic data corresponding to their molecular structures. They are thermally quite stable （≥ 300℃） and show strong circular dichroism signals in the visible spectral region owing to the helicity of the polyene backbone. The monosaccharide-containing polyacetylenes are cytophilic and can stimulate the growth of living cells.

关键词： Biocompatibility Biomimetic Helicity Monosaccharides Polyacetylenes Sugars.

Low-temperature strategy to synthesize single-crystal LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) with enhanced cycling performances as cathode material for lithium-ion batteries

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Nano Research 2022年第3期15卷 2052-2059页

作者： Fangya Guo y.ngfan xie youxiang Zhang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China

With high reversible capacities of more than 200 mAh/g,Ni-rich layered oxides Li[Ni_(x)Co_(y)Mn_(1–x–y)]O_(2)(x≥0.6)serve as the most promising cathode materials for lithium-ion batteries(LIBs).However,the anisotropic lattice volume changes linked to theirα-NaFeO_(2)structured crystal grains bring about poor cycle performances for conventionally produced NCM *** deal with these issue,single-crystalµm-sized LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)rods was synthesized by a hydrothermal *** with conventional synthesis methods,these LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)rods were calcined at a low temperature with excessive lithium sources,which not only reduces the sintering temperature but also ensures the mono-dispersed micrometer-scaled particle *** used as the cathode material for LIBs,the as-prepared LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2),with ordered layered-structure and low degree of cation mixing,shows excellent electrochemical *** sintered at 750°C with 50%Li-excess,the cathode material delivered an initial discharge capacity of 226.9 mAh/g with Coulombic efficiency of 91.2%at 0.1 C(1 C=200 mA/g)in the voltage range of 2.8‒4.3 *** charge-discharged at 1 C for 100 cycles,discharge capacity of 178.1 mAh/g with the capacity retention of 95.1%are still *** cycling stability at high cut-off voltage is also *** superior electrochemical properties should be related to the monodispersed micron scaled morphology which not only decreases the contact area between electrode and electrolyte but also mitigates the formation of *** low-temperature strategy of synthesizing single-crystal LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)rods should be able to provide a feasible method for synthesizing other single-crystal Ni-rich cathode materials with excellent electrochemical performances for LIB.

关键词： lithium ions batteries cathode excessive lithium single crystal LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)