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大尺度异形镂空浮体疲劳强度分析方法研究

舰船科学技术 2024年第9期46卷 99-105页

海洋环境复杂多变,海上结构物需长期承受随机波浪引起的交变载荷,极易产生疲劳破坏。本文以某海上大尺度异型镂空浮体为研究对象,通过计算分析找出了异形浮体结构容易产生疲劳破坏的位置。为使结构疲劳谱分析计算结果更加准确,本文提出... 详细信息

海洋环境复杂多变,海上结构物需长期承受随机波浪引起的交变载荷,极易产生疲劳破坏。本文以某海上大尺度异型镂空浮体为研究对象,通过计算分析找出了异形浮体结构容易产生疲劳破坏的位置。为使结构疲劳谱分析计算结果更加准确,本文提出一种数值规则波模拟法,用来计算浮体结构在工作时应力的传递函数。在此基础上,分别采用基于热点应力与名义应力的谱分析方法计算了浮体的疲劳寿命。结果显示,基于热点应力法得到的结构疲劳寿命略低于基于名义应力法得到的疲劳分析结果,更偏保守。以上研究结果可为大型海上浮式结构的设计提供参考。

关键词：大尺度异形镂空浮体疲劳数值规则波模拟法热点应力名义应力

Numerical investigation on the flow and power of small-sized multi-bladed straight Darrieus wind turbine

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1414-1421页

作者： JIANG Zhi-chao DOI Yasuaki zhang shu-you College of Mechanical and Energy Engineering Zhejiang University Hangzhou 310027 China Hangshen Holding Group Co.. Ltd Hangzhou 311234 China Graduate School of Engineering. Hiroshima UniversiO＇ Higashi-hiroshima Hiroshima 739-852 7 Japan

Straight Darrieus wind turbine has attractive characteristics such as the ability to accept wind from random direction and easy installation and maintenance. But its aerodynamic performance is very complicated,especially for the existence of dynamic stall. How to get better aerodynamic performance arouses lots of interests in the design procedure of a straight Darrieus wind turbine. In this paper,mainly the effects of number of blades and tip speed ratio are discussed. Based on the numerical investigation,an assumed asymmetric straight Darrieus wind turbine is proposed to improve the averaged power coefficient. As to the numerical method,the flow around the turbine is simulated by solving the 2D unsteady Navier-Stokes equation combined with continuous equation. The time marching method on a body-fitted coordinate system based on MAC (Marker-and-Cell) method is used. O-type grid is generated for the whole calculation domain. The characteristics of tangential and normal force are discussed related with dynamic stall of the blade. Averaged power coefficient per period of rotating is calculated to evaluate the eligibility of the turbine.

关键词：风轮机叶片气体流动功率系数

Hydroxyapatite/palmitic acid superhydrophobic composite coating on AZ31 magnesium alloy with both corrosion resistance and bacterial inhibition

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Frontiers of Materials Science 2024年第1期18卷 71-83页

作者： Hang zhang shu Cai Huanlin zhang Lei Ling you Zuo Hao Tian Tengfei Meng Guohua Xu Xiaogang Bao Mintao Xue Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education Tianjin UniversityTianjin 300072China Department of Orthopedic Surgery Spine CenterChangzheng HospitalNaval Medical UniversityShanghai 200003China

The coating-modified magnesium(Mg)alloys exhibit controllable corrosion resistance,but the insufficient antibacterial performance limits their clinical applications as degradable *** coatings show excellent performance in terms of both corrosion resistance and inhibition of bacterial adhesion and *** this work,a hydroxyapatite(HA)/palmitic acid(PA)superhydrophobic composite coating was fabricated on the Mg alloy by the hydrothermal technique and immersion *** HA/PA composite coating showed superhydrophobicity with a contact angle of 153°and a sliding angle of 2°.The coated Mg alloy exhibited excellent corrosion resistance in the simulated body fluid,with high polarization resistance(77.10 kΩ·cm^(2))and low corrosion current density((0.491±0.015)μA·cm^(-2)).Meanwhile,the antibacterial efficiency of the composite coating was over 98% against *** and *** in different *** results indicate that the construction of such superhydrophobic composite coating(HA/PA)on the Mg alloy can greatly improve the corrosion resistance of Mg alloy implants within the human body and avoid bacterial infection during the initial stages of implantation.

关键词： superhydrophobic coating hydroxyapatite corrosion resistance antibacterial

Distribution of pathogenic bacteria and antimicrobial sensitivity of eye infections in Suzhou

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 700-706页

作者： Li zhang Hai-zhang you Guo-Hui Wang Wei Xu Jian-Shan Li Qing-Liang Zhao shu Du Department of Hospital-Acquired Infection Control Lixiang Eye Hospital of Soochow UniversitySuzhou 215021Jiangsu ProvinceChina Department of Administrative Office Lixiang Eye Hospital of Soochow UniversitySuzhou 215021Jiangsu ProvinceChina Department of Clinical Laboratory Lixiang Eye Hospital of Soochow UniversitySuzhou 215021Jiangsu ProvinceChina Department of Pharmacy Lixiang Eye Hospital of Soochow UniversitySuzhou 215021Jiangsu ProvinceChina Department of Corneal and Lacrimal Passage Lixiang Eye Hospital of Soochow UniversitySuzhou 215021Jiangsu ProvinceChina Department of Fundus Diseases and Ocular Trauma Lixiang Eye Hospital of Soochow UniversitySuzhou 215021Jiangsu ProvinceChina

AIM:To investigate the types of bacteria in patients with eye infections in Suzhou and their drug resistance to commonly used antibacterial ***:The clinical data of 155 patients were retrospectively collected in this study,and the pathogenic bacteria species and drug resistance of each pathogenic bacteria were ***:Among the 155 patients(age from 12 to 87 years old,with an average age of 57,99 males and 56 females)with eye infections(160 eyes:74 in the left eye,76 in the right eye and 5 in both eyes,all of which were exogenous),71(45.81%)strains were gram-positive bacteria,23(14.84%)strains were gram-negative bacteria and 61(39.35%)strains were ***-positive bacteria were highly resistant to penicillin and erythromycin(78.87%and 46.48%respectively),but least resistant to vancomycin at ***-negative bacteria were highly resistant to cefoxitin and compound sulfamethoxazole(100%and 95.65%respectively),but least resistant to meropenem at *** of the resistance of gram-positive and gram-negative bacteria to some drugs revealed statistically significant differences(P<0.05)in the resistance of both to cefoxitin,cotrimoxazole,levofloxacin,cefuroxime,ceftriaxone and ceftazidime,and both had higher rates of resistance to gram-negative bacteria than to gram-positive *** distribution of bacterial infection strains showed that Staphylococcus epidermidis was the most common strain in the conjunctiva,cornea,aqueous humor or vitreous body and other eye ***,Fusarium and Pseudomonas aeruginosa were also among the most common strains of conjunctival and corneal ***:Gram-positive bacteria are the dominant bacteria in eye infections,followed by gram-negative bacteria and *** the resistance of gramnegative bacteria to multiple drugs,monitoring of bacteria should be strengthened in eye bacterial infections for effective prevention and control to reduce complications caused by eye infections.

关键词： eye infection pathogenic bacteria drug resistance antimicrobial sensitivity test

Chiral transmission by an open evolution trajectory in a non-Hermitian system

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Light(Science & Applications) 2024年第4期13卷 628-636页

作者： Xiaoqian shu Qi Zhong Kai Hong Oubo you Jian Wang Guangwei Hu Andrea Alù shuang zhang Demetrios N.Christodoulides Lin Chen Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China. Zhejiang Lab Hangzhou 311121China. CREOL College of Optics and PhotonicsUniversity of Central FloridaOrlandoFlorida 32816USA. Department of Physics The University of Hong KongHong KongChina. School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore. Photonics Initiative Advanced Science Research CenterCity University of New YorkNew YorkNY 10031USA. Shenzhen Huazhong University of Science and Technology Research Institute Shenzhen 518063China

Exceptional points(EPs),at which two or more eigenvalues and eigenstates of a resonant system coalesce,are associated with non-Hermitian Hamiltonians with gain and/or loss *** encircling of EPs has received significant interest in recent years,as it has been shown to lead to highly nontrivial phenomena,such as chiral transmission in which the final state of the system depends on the encircling ***,chiral transmission for a pair of eigenmodes has been realized by establishing a closed dynamical trajectory in parity-time-(PT-)or anti-PT-symmetric *** chiral transmission of symmetry-broken modes,more accessible in practical photonic integrated circuits,has been realized by establishing a closed trajectory encircling EPs in anti-PTsymmetric systems,the demonstrated transmission efficiency is very low due to path-dependent ***,we demonstrate chiral dynamics in a coupled waveguide system that does not require a closed ***,we explore an open trajectory linking two infinite points having the same asymptotic eigenmodes(not modes in PT-and anti-PT-symmetric systems),demonstrating that this platform enables high-efficiency chiral transmission,with each eigenmode localized in a single *** concept is experimentally implemented in a coupled silicon waveguide system at telecommunication *** work provides a new evolution strategy for chiral dynamics with superior performance,laying the foundation for the development of practical chiral-transmission devices.

关键词： chiral system symmetric

Discovery of the choristodere Hyphalosaurus baitaigouensis from the Lower Cretaceous Jiufotang Formation of western Liaoning,China and its paleobiogeographic significance

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Journal of Palaeogeography 2024年第3期13卷 547-562页

作者： Li-Jun zhang shu-An Ji Hai-Chun zhang South China Sea Culture Museum Hainan Tropical Ocean UniversitySanya 572022Hainan ProvinceChina Key Laboratory of Stratigraphy and Paleontology Ministry of Natural ResourcesInstitute of GeologyChinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008Jiangsu ProvinceChina

The water-living reptile genus Hyphalosaurus was previously discovered in the Lower Cretaceous Yixian Formation bearing the middle Jehol Biota in western Liaoning,*** complete skeletons of Hyphalosaurus are reported for the first time from the Jiufotang Formation bearing the late Jehol Biota at two sites in western *** show the typical characteristics of Hyphalosaurus baitaigouensis in terms of the contact between some cranial bones and the number of cervical and dorsal vertebrae,and therefore are assigned to *** discovery extends the stratigraphic range of this species from the Yixian Formation to the overlying Jiufotang *** paper further briefly compares the main characteristics of the two skeletons,summarizes the temporal and spatial distribution of Hyphalosaurus,and discusses the palaeogeographic evolution of western Liaoning at the middle and late Jehol Biota stages based on the aquatic habits of Hyphalosaurus and the geological background of western *** analytical results show that the volcanic downwarped lakes,with distinct geographical divisions in western Liaoning during the deposition of the Yixian Formation,had not completely disappeared till the deposition of the Jiufotang *** palaeo-lake in the Fuxin-Yixian Basin underwent the process of generation,expansion and shrinkage during the depositional period of the Yixian Formation and finally merged into a large *** palaeo-Dalinghe River,which connected the main basins in western Liaoning during the depositional period of the Jiufotang Formation,was formed simultaneously.

关键词： Western liaoning Jehol biota Jiufotang formation Hyphalosaurus baitaigouensis Palaeobiogeography

Cu-substituted nickel hexacyanoferrate with tunable reaction potentials for superior ammonium ion storage

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Journal of Materials Science & Technology 2024年第2期169卷 19-27页

作者： Leiyu Fan Guangchang shu Yiwen Liu Haoxiang Yu Lei Yan Liyuan zhang Jie shu School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China

In this work,a variety of Cu_(x)Ni_(2-x)Fe(CN)_(6)(x=0,0.4,0.8,1.2,1.6,2)cathodes for ammonium ion batteries are prepared and their electrochemical performances are *** the introduction of copper in nickel hexacyanoferrate,the electrochemical performance varies without changing the structure of nickel *** increase of Cu content in nickel hexacyanoferrate leads to the enhancement of reaction potential and *** results suggest that the substitution of Cu for Ni has a positive effect on improving the cycling stability and rate capacity of nickel hexacyanoferrate when x in Cu_(x)Ni_(2-x)Fe(CN)_(6)is less than ***,Cu_(0.4)Ni_(1.6)Fe(CN)_(6)exhibits the best cycling per-formance(capacity retention of 97.54%at 0.3 C)and the highest rate capacity(41.4 mAh g^(-1)at 10 C)in Cu_(x)Ni_(2-x)Fe(CN)_(6).Additionally,the X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)tests also reveal that the structural evolution of Cu_(0.4)Ni_(1.6)Fe(CN)_(6)is highly reversible upon NH_(4)^(+)***,this work proposes a candidate material for ammoniumion batteries and offers a novel avenue for adjusting the operating potential of the material.

关键词： Nickel hexacyanoferrate Copper hexacyanoferrate NH_(4)^(+)storage Ammonium ion batteries Aqueous batteries

Highly anti-corrosive NiFe LDHs–NiFe alloy hybrid enables long-term stable alkaline seawater electrolysis

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Rare Metals 2024年第9期43卷 4321-4332页

作者： Jia-Hong Li Hao Chen Si-Hang you Gan-Xin Yang Peng Liu Meng-Qi Gao shu-Guang Chen Fei-Fei zhang School of Materials Science and Engineering Changsha University of Science and Technology Department of Materials Science and Engineering Faculty of Engineering National University of Singapore School of Materials Science and Engineering Jilin University

Owing to the signi?cant potential of alkalin seawater electrolysis for converting surplus power into eco friendly hydrogen fuel,we developed bifunctional elec trodes that integrate low-crystalline NiFe LDHs and amorphous NiFe alloy on a Ni foam （NF） substrate to enhance this *** by the battery-like charac teristics of NiFe LDHs,an anti-corrosive and active oute layer of NiFevacOOH continuously forms over time in th hybrid on the anode for the oxygen evolution reaction（OER）,effectively mitigating powder shedding caused by corrosion induced by multiple anions in *** while,the strong bond between the hybrid and the NF substrate maintains intact hybrid coatings to ensure a rel atively high overall conductivity of the electrodes,signif icantly reducing the negative effects of structura degradation during the OER and hydrogen evolution reaction （HER）,as well as the accumulation of contami nants on the electrode *** long-term tests,thes bifunctionalhybridelectrodesmaintained stable performance,even at a high current density o500 mA·*** cell voltage increased by only 88 m V over 1000 h to 1.970 V during saline electrolysis and by103 mV over 500 h to 2.062 V during seawater electroly ***,this study provides valuable insights into ef?cient and stable seawater electrolysis using NiFe LDHs–NiFe alloy hybrids.

关键词： Bifunctional Corrosion NiFe LDHs Seawater electrolysis Stability

CuInS_(2)quantum-dot-modified g-C_(3)N_(4)S-scheme heterojunction photocatalyst for hydrogen production and tetracycline degradation

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Journal of Materials Science & Technology 2024年第5期172卷 145-155页

作者： Jingjing zhang Yue Zhao Kezhen Qi shu-yuan Liu College of Pharmacy Dali UniversityDali 671000China Department of Pharmacology Shenyang Medical CollegeShenyang 110034China

CuInS_(2)quantum-dot(CIS QD)-modified g-C_(3)N_(4)(CN)catalysts(CIS/CN)were prepared with the aid of an in-situ growth *** as-obtained photocatalysts were explored by measuring their crystallinity,surface morphology,binding energy and light absorption *** photocatalytic efficiency of the pho-tocatalysts was evaluated through photocatalytic water splitting for hydrogen production and tetracycline(TC)antibiotic degradation under the simulated solar light and visible light *** optimized sample(10CIS/CN)showed the best photocatalytic activity:producing 102.4μmol g^(-1)h^(-1)of hydrogen in 1 h,or degrading 52.16%of TC in 120 min,which were respectively 48 or 3.4 times higher than the photocatalytic activity of CN *** enhancement in the efficiency of the composite system was prin-cipally accredited to the enlargement of light absorption,the more effective in charge transfer and the dropping of the charge carrier pair recombination through a formed S-scheme heterojunctional *** work is an effort to adjust CN-based polysulfide QD for speedy *** enriched photo-catalytic activity grants a new sense for adjusting the optical properties of CN.

关键词： CuInS_(2)QDs g-C_(3)N_(4) Photocatalysis Hydrogen production S-scheme heterojunction