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Acta Metallurgica Sinica(English Letters) 2016年第3期29卷 228-236页

作者： Manuela Stan Adriana Popa dana Toloman Teofil-Danut Silipas Dan Cristian Vodnar National Institute for Research and Development of Isotopic and Molecular Technologies 67-103 Donat 400293Cluj-Napoca Romania Department of Food Science and Technology University of Agricultural Sciences and Veterinary Medicine 3-5 ManasturStreet 400372 Cluj-Napoca Romania

ZnO nanoparticles（ZnO NPs） were synthesized by chemical method（coprecipitation） and biological method using aqueous extracts of garlic（Allium sativum）,rosemary（Rosmarinus officinalis） and basil（Ocimum basilicum）.The influence of plant extract on the antibacterial and antioxidant activities of green synthesized nanoparticles was *** X-ray diffraction studies reveal that all ZnO samples have hexagonal wurtzite *** particle size of ZnO NPs estimated by transmission electron microscopy analysis（between 14 and 27 nm） varies depending on the synthesis method of nanoparticles and the type of extracts from the plants *** functional groups involved in the biosynthetic procedure were evidenced by Fourier transform infrared *** presence of Mn^（2＋）ions,Zn vacancy complexes and oxygen vacancies in ZnO samples was highlighted by electron paramagnetic resonance *** green synthesized ZnO NPs have shown a good bactericidal activity against Staphylococcus aureus,Bacillus subtilis,Listeria monocytogenes,Escherichia coli,Salmonella typhimurium and Pseudomonas aeruginosa bacterial *** NPs synthesized using extracts of the selected plant species have been found to exhibit more enhanced antibacterial and antioxidant activities as compared to chemical ZnO NPs.

关键词： Zinc oxide nanoparticles Antioxidant activity Antibacterial activity Green synthesis Plant extracts

Deep Feature Extraction and Feature Fusion for Bi-Temporal Satellite Image Classification

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Computers, Materials & Continua 2021年第1期66卷 373-388页

作者： Anju Asokan Bogdan Patrut dana Danciulescu D.Jude Hemanth Department of ECE Karunya Institute of Technology and SciencesCoimbatoreIndia Department of Computer Science Alexandru Ioan Cuza University of la?ila?iRomania Department of Computer Science University of CraiovoCraiovoRomania

Multispectral images contain a large amount of spatial and spectral data which are effective in identifying change *** feature extraction is important for multispectral image classification and is evolving as an interesting research area in change ***,many deep learning framework based approaches do not consider both spatial and textural details into *** order to handle this issue,a Convolutional Neural Network(CNN)based multi-feature extraction and fusion is introduced which considers both spatial and textural *** method uses CNN to extract the spatio-spectral features from individual channels and fuse them with the textural *** the fused image is classified into change and unchanged *** presence of mixed pixels in the bitemporal satellite images affect the classification accuracy due to the misclassification *** proposed method was compared with six state-of-theart change detection methods and *** main highlight of this method is that by taking into account the spatio-spectral and textural information in the input channels,the mixed pixel problem is *** indicate the effectiveness of this method and demonstrate that it possesses low misclassification errors,higher overall accuracy and kappa coefficient.

关键词： Remote sensing convolutional neural network deep learning multispectral bitemporal change detection

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基于随机算法的纤维材料过滤特性仿真分析

纺织学报 2022年第9期43卷 76-81页

作者：诸文旎徐润楠胡蝶飞姚菊明 MILITKY Jiri KREMENAKOVA dana 祝国成浙江理工大学纺织科学与工程学院(国际丝绸学院) 浙江杭州310018 浙江理工大学材料科学与工程学院浙江杭州310018 浙江理工大学浙江-捷克先进纤维材料联合实验室浙江杭州310018 宁波大学材料科学与化学工程学院浙江宁波315201 利贝雷茨理工大学纺织工程学院捷克利贝雷茨46117

为分析纤维空气过滤材料的流场演变情况,综合过滤效率及颗粒流动轨迹,基于随机算法建立了纤维空气过滤材料的三维模型,并采用计算流体力学中的欧拉-拉格朗日离散相模型,在雷诺相似准则的基础上研究了微米纤维介质中的气固流动特性。结... 详细信息

为分析纤维空气过滤材料的流场演变情况,综合过滤效率及颗粒流动轨迹,基于随机算法建立了纤维空气过滤材料的三维模型,并采用计算流体力学中的欧拉-拉格朗日离散相模型,在雷诺相似准则的基础上研究了微米纤维介质中的气固流动特性。结果表明:入口速度变化对流场压力与速度场分布有明显影响,随着入口速度增大,阻滞区域面积增加,流场空隙处更易形成高速流动与速度漩涡,同时流场整体速度差增大,压力损失与入口速度呈正相关;纤维模型对平均粒径为8~18 mm颗粒的过滤效率较为稳定,均在80.4%~84%,在入口速度为2 m/s工况下,过滤效率与粒径接近正比例关系。

关键词：空气过滤数值模拟相似准则过滤特性离散相模型纤维材料

Hyperelastic Membrane Actuators:Analysis of Toroidal and Helical Multifunctional Configurations

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Cyborg and Bionic Systems 2022年第1期2022卷 129-140页

作者： Eduardo Perez-Guagnelli Joanna Jones dana D.Damian Department of Automatic Control and Systems Engineering Universty of Shefield UK

Technologies that providemechanical assistance arerequired inthemdicalfeld,such asimplants that regenerate tssuethroughelongation and *** ofthe challenges is to develop actuators that combinethe benefits ofhigh axialextension at lowpressures,modularity,multifunction,and load bearing capabilities into one design while maintaining their shape and *** such a challenge wll provide implants with enhanced capacity for mechanical assistance to induce *** introduce two novel actuators(M2H)built of stacked Hyperelastic Balloning Membrane Actuators(HBMAs)that can be realized using helical and toroidal *** restraining the HBMA expansion deterministicallyusing a semisoft exoskeleton,the actuatorsors areendoweded withh axial extension and radial expansion *** actuatorsare thus built of modules that canconfiguured different therapeutical needs and multifunctionality,to provideanatomically congruent *** desigl,fabricationtestin;and numerical and experimental validation ofthe *** can aaxiallyind6 in their helicaland toroidal configurations at input pressuresas low as 26 and 24 kPa,*** the axial module is used separately,its extension capacity reaches>170%.The M2H-HBMAs can perform independent and simultaneousxpansion and extension motions with negligible intraluminaldeformation as well as stand at least 1kg of axial force without *** M2H-HBMAs overcome the limitations ofhyperexpanding machines that show low resistance to *** envisage M2H-HBMAs as promising tools to perform tisueregeneration procedures.

关键词： restrain overcome skeleton

Reproducibility of Test-Retest Cortical Evoked Responses in Patients with Focal Epilepsy

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Journal of Behavioral and Brain Science 2023年第1期13卷 1-13页

作者： Mackenzie C. Cervenka Monika Rozycka Erik Sass dana Boatman Reich Department of Neurology Johns Hopkins School of Medicine Baltimore USA Department of Otolaryngology Johns Hopkins School of Medicine Baltimore USA

This exploratory study examined the short-term reliability of cortical auditory evoked responses recorded from patients undergoing whole-head scalp elec-troencephalography (EEG) monitoring to assess their candidacy for surgical treatment of intractable focal seizures. Participants were 26 patients with either left-sided (N = 13) or right-sided focal epilepsy admitted to the hospital for continuous scalp EEG monitoring for possible epilepsy surgery planning. Cortical auditory evoked responses were recorded over multiple days from scalp EEG electrodes using tones presented binaurally in a passive oddball paradigm. Test-retest intervals were 1 - 6 days (mean 2 days). Test-retest reproducibility of the auditory N1 response was assessed by paired t-test (latency) and cross-correlation analysis (amplitude and latency). Within-patient comparisons of test-retest auditory N1 peak latencies revealed no significant differences. The cross-correlation coefficient indicated high test-retest reproducibility of the N1 waveform (rcc = 0.88). Seizure lateralization was not associated with asymmetries in N1 latencies or amplitudes. An N1 amplitude asymmetry (right > left) in patients with focal seizures originating from the left hemisphere was initially observed, but disappeared when patients with prior resections were excluded, suggesting that reduced left hemisphere tissue volume may account for the smaller N1 amplitudes. Test-retest reliability of cortical auditory evoked responses was unexpectedly high in patients with focal epilepsy regardless of seizure lateralization or localization. These findings challenge the view that neural responses are intrinsically unstable (unreliable) in patients with seizures.

关键词： Auditory Evoked Response Seizure Epilepsy Reproducibility Reliability

超宽调谐(2.6~5μm)中红外皮秒脉冲激光的研究

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新疆师范大学学报（自然科学版） 2024年第4期43卷 20-25页

作者：买里克古丽·艾合买提达娜·加山尔杜力坤·苏来曼塔西买提·玉苏甫新疆师范大学物理与电子工程学院新疆发光矿物与光功能材料研究重点实验室新疆乌鲁木齐830054

在超快脉冲激光中,超宽调谐通常应用于超连续谱产生、光谱分析和调制等多个领域。文章利用皮秒脉冲同步泵浦技术,搭建了一种基于MgO:PPLN晶体的“Z”形光参量振荡器,通过具有扇形周期极化的晶体在中红外波段产生了高功率、波长超宽调谐(... 详细信息

在超快脉冲激光中,超宽调谐通常应用于超连续谱产生、光谱分析和调制等多个领域。文章利用皮秒脉冲同步泵浦技术,搭建了一种基于MgO:PPLN晶体的“Z”形光参量振荡器,通过具有扇形周期极化的晶体在中红外波段产生了高功率、波长超宽调谐(2.6~5μm)的皮秒脉冲激光源输出。该振荡器由五镜一晶体组成,这五镜片的选择和精确调整是提高光参量振荡器输出性能的关键因素,采用波长为1.064μm的Nd:YVO_(4)皮秒脉冲激光源,选择周期在26~32μm可调谐的MgO:PPLN晶体,最大泵浦功率为15W时,2.66μm、3.44μm和4.99μm处获得了最大输出功率分别为3.41W、2.78W和0.52W的闲频光,相应的光-光转换效率分别为58%、55%、15%,测量到中红外光谱谱宽为2.37nm(2615nm)、Δλ=1.87nm(3687nm)、Δλ=1.30nm(4992nm),观察到在没有任何窄化光学元件条件下长脉冲随波长光谱谱宽具有线性变窄的过程。在2.6~4.5μm波段的激光输出功率均大于1W,实现了高功率,波长超宽调谐的中红外皮秒激光的连续输出。窄谱宽超宽调谐中红外皮秒脉冲激光为超快过程研究和应用领域提供了一种强大的工具。通过优化波长调谐范围和脉冲宽度能够满足不同领域对中红外激光的高要求,对推动相关领域的研究和发展至关重要。

关键词：中红外激光同步泵浦光参量振荡器 MgO:PPLN晶体波长宽调谐皮秒脉冲

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Using Vetiver grass technology for mitigating sediment loads in the Talakhaya Watershed areas in Rota, CNMI

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International Soil and Water Conservation Research 2018年第2期6卷 194-201页

作者： Mohammad HGolabi Sydonia Manibusan Timothy Righetti dana Okano Clancy Iyekar University of Guam USA National Oceanic and Atmospheric Administration CNMIUSA

Talakhaya watershed in Rota is identified as a Coral Reef Management Priority site for CNMI (Com-monwealth of Northern Mariana Islands). In 2010 federal and jurisdictional partners developed a Con-servation Action Plan (CAP) for the Talakhaya Watershed. The goal of this initial Watershed Soil Loss Assessment therefore, was to assist in evaluating the re-vegetation objectives of 'Mitigating Sediment Load' in the Talakhaya watershed by making a thorough characterization of its main river systems. The objectives of this project were to reach those goals by measuring the hydrological parameters following the installation and the use of water meters, barometric level loggers, turbidity meters and rain gauges. The water flow as well as the turbidity level of each stream leading to the ocean from the Talakhaya Watershed was measured and sedimentation level was assessed accordingly. The results from the monitoring of the watershed conducted during the project timeline reported here show that all four rivers under study have statistically different stage-discharge curves. The river's relationship between time and turbidity also vary especially in the summer months of the first-year observations. Linear and convex polynomial relationships were sometimes observed in the different rainfall groupings for the four river systems, however relationships were often not significant. This-being-said, Quantile Regressions suggest that when data from all four river systems are combined for cases where there is some de-tectable rainfall, a maximum possible turbidity level can be defined.

关键词： Watershed Management Vetiver grass system Coral Badlands Micronesia Rota CNMI

面向哈萨克斯坦汉语教材本土化研究——以《新实用汉语课本（俄文版）》为例

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面向哈萨克斯坦汉语教材本土化研究——以《新实用汉语课本（俄文...

作者：晶晶（Dyussembayeva dana）华中师范大学

学位级别：硕士

随着全球化的进展,中国和哈萨克斯坦的关系得到迅速发展,很多哈萨克斯坦人对中国文化感兴趣,开始学习汉语。哈萨克斯坦有很多大学开设了中文专业,《新实用汉语课本》在哈萨克斯坦得到非常好的应用,目前在哈萨克斯坦比较流行的汉语教材... 详细信息

随着全球化的进展,中国和哈萨克斯坦的关系得到迅速发展,很多哈萨克斯坦人对中国文化感兴趣,开始学习汉语。哈萨克斯坦有很多大学开设了中文专业,《新实用汉语课本》在哈萨克斯坦得到非常好的应用,目前在哈萨克斯坦比较流行的汉语教材主要是俄语版的教材,俄版的教材大多是若干年前从中国版翻译过去,再根据俄国汉语教学和学生的具体需要加以改动。因其有俄语翻译,从俄汉比较角度诠释语法,对大多懂俄语的哈萨克斯坦学生比较方便,因此在哈国汉语教学中很是通行。虽然在哈萨克斯坦,俄语和哈萨克语都是官方语言,但是当前的汉语教材依然不能完全满足教学的实际需要。基于这种情况,“本土化”教材的需求应时而生。本文以《新实用汉语课本(俄文版)》为研究对象,主要研究该课本在哈萨克斯坦的适用性以及存在的一些本土化的问题,研究分为五个部分。第一部分绪论,提出本文研究背景和意义,相关问题研究现状及研究方法。第二部分为理论基础,分析该套的编写情况和使用情况,提出跨文化交际、构建主义、第二语言习得等相关理论基础。第三部分为该套教材本土化问题的考察;由于哈萨克斯坦学生是在非目的语环境下学习汉语,为了让学生更好的理解中国文化,本土化教材需要相应的编写一些与中国文化相类似的文化知识,方便学生通过对哈萨克斯坦本土化文化的了解去理解一些中国文化,因此本文从语音、词汇、语法及课文四个部分分析该教材在本土化方面存在的问题,得出该套教材在语音注释上缺少中俄发音对比,在词汇上缺少一些哈萨克斯坦的本土词汇,在课文内容上同样缺乏让哈萨克斯坦学生感兴趣的本土化的课文内容,在语法知识点上缺乏中俄语法的对比,这些都会导致哈萨克斯坦学生学习汉语时存在一些问题。第四部分采用问卷调查的方式调查哈萨克斯坦的学生对该教材调查教材的适用性问题,并针对以上分析和调查出的一些问题从语音、词汇、语法以及课文等四大块内容提出本土化教材编写的一些建议。第五部分为结论,分析总结本文的研究内容并提出展望。本文从实际出发,以《新实用汉语课本(俄文版)》为考察对象,通过分析该教材内容并调查该教材在哈萨克斯坦的使用情况,提出教材在本土化方面存在的问题,为汉语本土化的编写提供了一些建议,以促进汉语教材的发展和建议,进一步提高并帮忙哈萨克斯坦汉语学习者教材的编写质量,从另一个角度丰富了本土化教材的研究。

关键词：哈萨克斯坦《新实用汉语课本(俄文版)》本土化教材教材编写

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First Principle Study on the Rectification of Molecular Junctions Based on the Thiol-ended Oligosilane

作者： edited by dana Richards.

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Chinese Journal of Structural Chemistry 2015年第6期34卷 813-821页

作者： ZHANG Rong-Fang YANG E LI Yi LIN Li-Xiang LING Qi-dana College of Materials Science & Engineering Fujian Normal University College of Chemistry Fuzhou University

The electron transport properties of various molecular junctions based on the thiol-ended oligosilane are investigated through density functional theory combined with non-equilibrium Green＇s function formalism. Our calculations show that oligosilanes doped by the phenyl and -C10H6 groups demonstrate better rectifying effect and their rectification ratios are up to 15.41 and 65.13 for their molecular junctions. The current-voltage （I-V） curves of all the Au/ modified oligosilane/Au systems in this work are illustrated by frontier molecular orbitals, transmission spectra and density of states under zero bias. And their rectifying behaviors are analyzed through transmission spectra.

关键词： first principle thiol-ended oligosilane rectification