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三峡水库不同区域对鱼类群落结构和鱼类组成动态的影响(英文)

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水生生物学报 2014年第3期38卷 438-445页

作者： H.A.C.C.Perera 李钟杰 s.s.de silva 张堂林苑晶叶少文夏雨果刘家寿中国科学院水生生物研究所淡水生态与生物技术国家重点实验室武汉430072 中国科学院大学北京100049 school of Ecology and Life sciences Deakin UniversityWarrnamboolVIC 3280Australia

研究选取三峡水库三个不同的区域来研究离坝距离对鱼类群落结构和鱼类组成动态的影响。2010年11月到2011年10月期间共采集了8680尾鱼类样本,隶属于11科58种,其中鲤科鱼类占据了三峡水库鱼类的主体。夏季时的鱼类丰度显著高于其他季节的(... 详细信息

研究选取三峡水库三个不同的区域来研究离坝距离对鱼类群落结构和鱼类组成动态的影响。2010年11月到2011年10月期间共采集了8680尾鱼类样本,隶属于11科58种,其中鲤科鱼类占据了三峡水库鱼类的主体。夏季时的鱼类丰度显著高于其他季节的(P<0.05)。鱼类物种多样性与丰度在靠近大坝的江段(秭归)最低,中游江段(万州)相对较高,远离大坝的江段(涪陵)居中。随着三峡大坝的建成,鱼类区系也由适应流水生存的种类转变为适应静水生存的种类。因此,三峡水库蓄水已经明显地改变了其原有的鱼类群落结构,鱼类组成的相对丰度也随着时间发生了改变。

关键词：鱼类区系转变蓄水物种多样性三峡水库长江

鲻鱼(Mugil cephalus L.)幼鱼生物学的研究——Ⅰ、盐度对摄食、生长和食物转换的影响

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国外水产 1979年第1期 18-24页

作者： s.s.de silva P.A.B.Perera 葛国昌

研究了不同的盐度(30‰、20‰、10‰和<1‰)对于鲻鱼(Mugil cephalus L.)幼鱼(以下称幼鲻)生长、摄食和食物转换效率的影响。我们发现四种盐度实验中的日摄食量变动很大。当投入过量食物时,摄食量主要取决于盐度。在投饵量为体重的8%或... 详细信息

研究了不同的盐度(30‰、20‰、10‰和s L.)幼鱼(以下称幼鲻)生长、摄食和食物转换效率的影响。我们发现四种盐度实验中的日摄食量变动很大。当投入过量食物时,摄食量主要取决于盐度。在投饵量为体重的8%或过量时,生长率没有大的差别。盐度为20‰时生长率最高。盐度为10‰过量投饵时,鲻鱼的食物转换效率的百分比最高。按定量投饵时,食物的转换效率随着盐度的提高而降低。

关键词：摄食量鱼类生长速度投饵量水生动物 Mugil cephalus L 食物转换效率鲻鱼生物学

鲻鱼(Mugil cephalus L.)幼鱼生物学的研究——Ⅱ、饵料和摄食

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国外水产 1979年第1期 25-32页

作者： s.s.de silva M.J.s.Wijeyaratne 雷霁霖

本文是进行幼鲻(鲻鱼幼鱼—Mugil cephalus L.)生物学调查的第二篇报告,阐述了鲻鱼在斯里兰卡沿岸和河口水域中养殖的可能性。作者从1974年11月至1975年10月对沿岸纳贡博(Negombo)湖(北纬7°10′,东经79°50′)捕来的体长为20—55毫米... 详细信息

本文是进行幼鲻(鲻鱼幼鱼—Mugil cephalus L.)生物学调查的第二篇报告,阐述了鲻鱼在斯里兰卡沿岸和河口水域中养殖的可能性。作者从1974年11月至1975年10月对沿岸纳贡博(Negombo)湖(北纬7°10′,东经79°50′)捕来的体长为20—55毫米的幼鲻进行了饵料和摄食习性的研究。援食强度,即为计算在每个摄食个体的胃含物中所有饵料生物的数目。幼鲻从4月以后,随着季节的变迁而增加摄食强度,至7—8月份达到高峰。有超过80%的个体全年摄食。饵料(胃含物)由18个属的硅藻、8个属的绿藻、一些鼓藻(desmids—chlor-phyceae)、6个属的蓝绿藻和8种其他饵料所组成。体长小于25毫米的幼鲻胃中没有发现沙粒或有机碎屑。有机碎屑和沙粒出现的百分比是随体长的增长而增加的。就质量而言,硅藻是最好的饵料品种,因为它超过整个饵料的50%。虽然在饵料中只发现黄藻类(Xanthophyceae)的一个属,而它的作用是重要的。我们发现幼鲻每天有定期的摄食活动,其摄食高峰出现在黎明和靠近中午并与潮汐的状况无关。幼鲻各生长期的饵料和摄食行为,就我们调查所得的资料,对24小时内出现的二个摄食高峰和饵料种类的重要性进行了评价,并对鲻鱼和其他植物食性鱼类混养的可能性作了简要的讨论。

关键词：饵料生物摄食习性 Mugil cephalus L 摄食强度有机碎屑体长鲻鱼幼鱼生物学

supercritical fluid technology as a sustainable alternative method for textile dyeing:An approach on waste,energy,and CO_(2)emission reduction

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Journal of Environmental sciences 2024年第6期140卷 123-145页

作者： Carlos Rafael silva de Oliveira Patrícia Viera de Oliveira Leandro Pellenz Catia Rosana Lange de Aguiar Afonso Henrique da silva Júnior Federal University of santa Catarina Textile Engineering Department2514 João Pessoa St.BlumenauSC89036-004Brazil Federal University of santa Catarina Chemical Engineering DepartmentS/n Biotério Central St.FlorianópolisSC88040-900Brazil

The clothing industry is considered one of the most polluting industries on the planet due to the high consumption of water,energy,chemicals/dyes,and high generation of solid waste and *** with environmental concerns,the textile ennoblement sector is the most critical of the textile production chain,especially the traditional dyeing *** an alternative to current problems,dyeing with supercritical CO_(2)(scCO_(2))has been presented as a clean and efficient process for a sustainable textile *** fluid dyeing(sFD)has shown a growing interest due to its significant impact on environmental preservation and social,economic,and financial *** main sFD benefits include economy and reuse of non-adsorbed dyes;reduction of process time and energy expenditure;capture of atmospheric CO_(2)(greenhouse gas);use and recycling of CO_(2)in sFD;generation of carbon credits;water-free process;effluent-free process;reduction of CO_(2)emission and auxiliary *** being still a non-scalable and evolving technology,sFD is the future of *** review presented a comprehensive overview of the environmental impacts caused by traditional processes and confronted the advantages of *** sFD technique was introduced,along with its latest advances and future *** and environmental gains were also discussed.

关键词： Textile industry supercritical dyeing sustainable processes Water free dyeing Energy saving Cleaner production

Adsorption of yttrium(Y^(3+)) and concentration of rare earth elements from phosphogypsum using chitin and chitin aerogel

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Journal of Rare Earths 2024年第4期42卷 775-782页

作者： Glaydson s.dos Reis Diana Pinto sabrina F.Lütke Eder C.Lima Luis F.O.silva Irineu A.s.de Brum Guilherme L.Dotto department of Forest Biomaterials and Technology Biomass Technology Centre Swedish University of Agricultural SciencesUmeaE13Swedn Universidad de La Costa Calle 58#55-66080002BarranquillaAtlanticoColombia Research Group on Adsorptive and Catalytic Process Engineering(ENGEPAC) Federal University of Santa MariaAv.Roraima100079705900Santa MariaRSBrazil Institute of Chemistry Federal University of Rio Grande do Sul90040060Porto AlegreBrazil

Chitin powder and chitin-aerogel were prepared from shrimp wastes and used to uptake Y^(3+)from aqueous solutions and concentrate this rare earth element from phosphogypsum(PG).Chitin aerogel displays a specific surface area of 945 m^(2)/g,while chitin powder is 3.6 m^(2)/g,which largely influences its adsorption *** the adsorption in synthetic solutions,the effect of pH on Y^(3+)removal is strong for chitin powder *** contrast,no big pH influence was detected for chitin *** interactions and chelation can highlight the proposed mechanism of Y^(3+)on chitin adsorbents for the powder and ***,in addition to these interactions,pore filling/pore diffusion is the main mechanism of Y^(3+)removal in the chitin *** aerogel is efficient in concentrating 8 times the Y^(3+)from PG,a very complex *** complex chitin aerogel-Y^(3+)can be a secondary source of rare earth elements for other applications.

关键词： Rare earths sustainable material Chitin powder Chitin porous aerogel Yttrium adsorption and recovery

Rotating effects on the photoionization cross-section of a 2D quantum ring

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Communications in Theoretical Physics 2024年第10期76卷 153-159页

作者： Carlos Magno O Pereira Frankbelson dos s Azevedo Luís Fernando C Pereira Edilberto O silva departamento de Física Universidade Federal do Maranh?o

In this article, we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame, taking into account the Aharonov–Bohm(AB) effect and a uniform magnetic field. Our analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the system. solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, providing a clear expression for the energy levels. Furthermore,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. specifically, we evaluate the photoionization cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoionization process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

关键词： Aharonov-Bohm effect photoionization cross-section quantum ring rotating effect

Analysis of a passive ankle exoskeleton for reduction of metabolic costs during walking

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defence Technology（防务技术） 2024年第7期37卷 62-68页

作者： Luís Quinto Pedro Pinheiro sergio B.Goncalves Ivo Roupa Paula simoes Miguel Tavares da silva CINAMIL Academia MilitarInstituto Universitario MilitarLisbonPortugal IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal

Modern conflicts demand substantial physical and psychological exertion,often resulting in fatigue and diminished combat or operational *** exoskeletons have been developed recently to address these challenges,presenting various limitations that affect their operational or everyday *** article evaluates the performance of a dual-purpose passive ankle exoskeleton developed for the reduction of metabolic costs during walking,seeking to identify a force element that could be applied to the target *** on the 6-min walk test,twenty-nine subjects participated in the study using three different force *** results indicate that it is possible to reduce metabolic expenditure while using the developed ***,the comfort and range of motion results verify the exoskeleton's suitability for use in uneven terrain and during extended ***,the choice of the force element should be tailored to each user,and the control system should be adjustable to optimise the exoskeleton's performance.

关键词： Ankle passive exoskeleton Metabolic cost reduction Dual-use exoskeleton Gait Biomechanics

A functional gel polymer electrolyte based on PVDF-HFP/gelatin toward dendrite-free lithium metal batteries

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Nano Research 2024年第4期17卷 2790-2799页

作者： Xiaoyi Hu Kangli Liu shijie Zhang Guosheng shao s.Ravi P.silva Peng Zhang state Center for International Cooperation on designer Low-carbon and Environmental Materials(CDLCEM) School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China Zhengzhou Materials Genome Institute(ZMGI) ZhongyuanzhiguXingyang 450100China Nanoelectronics Center Advanced Technology InstituteUniversity of SurreyGuildfordGU27XHUK

The leakage of liquid electrolyte and the formation of lithium dendrites pose challenges to safety and stability of lithium metal batteries(LMBs).The appearance of gel polymer electrolyte(GPE)has obviously improved the safety of traditional ***,the limited inhibition of GPE on lithium dendrites is detrimental to the safety of ***,a kind of poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)/gelatin(GN)GPE with high ionic conductivity,high-temperature resistance,and flame-retardancy,was prepared by electrospinning and soaking *** the electrospinning network of PVDF-HFP,its affinity to liquid electrolytes,makes this GPE more beneficial to ions transport and the formation of ***,the GN with sol–gel properties,enhances the mechanical property(13.5 MPa)of HFP-GN ***,X-ray photoelectron spectroscopy(XPs)and density functional theory(DFT)suggest that the attraction of polar groups of GN to Li+can regulate the distribution of Li+and protect Li ***,the application of HFP-GN GPEs to LMBs with cathodes of LiFePO_(4) and LiCoO_(2) deliver excellent electrochemical performances:after 300 cycles,the LiFePO_(4)/HFP-GN GPE/Li battery keeps a low capacity decay rate of 0.09%at 5 C;after 400 cycles at 2 C,the LiCoO_(2)/HFP-GN GPE/Li cell retains a high capacity retention of 74%.This GPE is demonstrated for the application prospect of safe LMBs.

关键词： poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP) gelatin polar groups lithium metal battery lithium dendrite

synthesis of coral-like structures of Pr-Yb co-doped YIG: structural,optical, magnetic and antimicrobial properties

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Journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.Guerra s.Castro-Lopes J.Matilla-Arias Idglan s.de Lima Edson C.silva-Filho Josy A.Osajima F.Guerrero R.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDs) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against s. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties