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Science China Chemistry 2016年第7期59卷 843-847页

作者： xiang wo Yashuang Luo Nongjian Tao Wei Wang Hong-Yuan Chen State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical Engineering Nanjing University Nanjing 210023 China

Molar concentration of gold nanoparticles is one of the most critical parameters of gold colloids in order to develop their applications in sensing, diagnostics and nanomedicine. Previous methods often stand just for gold nanoparticles with regular shape and narrow size distribution. In the present work, we proposed an absolute quantification method that determined the molar concentration of gold nanoparticles with arbitrary shapes and polydisperse sizes. This approach involved the real time monitoring and counting of individual nanoparticles collision events, from which the quantification of molar concentration was achieved using a theoretical model consisting of Fiek＇s laws of diffusion and Stokes-Einstein equation. The determination of spherical gold nanoparticles concentration resulted in excellent agreement with traditional spectrometry method. It was further demonstrated that the present approach can be expanded to determine the molar concentration of gold nanoparticles with arbitrary shapes and poly-diversed distributions.

关键词： number concentration gold nanoparticles surface plasmon resonance microscopy

Binary neutron stars gravitational wave detection based on wavelet packet analysis and convolutional neural networks

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Frontiers of physics 2020年第2期15卷 111-117页

作者： Bai-Jiong Lin xiang-Ru Li wo-Liang Yu South China Normal University Guangzhou 510631China

This work investigates the detection of binary neutron stars gravitational wave based on convolutional neural network(CNN).To promote the detection performance and efficiency,we proposed a scheme based on wavelet packet(WP)decomposition and *** WP decomposition is a time-frequency method and can enhance the discriminant features between gravitational wave signal and noise before *** CNN conducts the gravitational wave detection by learning a function mapping relation from the data under being processed to the space of detection *** function-mapping-relation style detection scheme can detection efficiency *** this work,instrument effects are con-sidered,and the noise are computed from a power spectral density(PSD)equivalent to the Advanced LIGO design *** quantitative evaluations and comparisons with the state-of-art method matched filtering show the excellent performances for BNS gravitational wave *** efficiency,the current experiments show that this WP-CNN-based scheme is more than 960 times faster than the matched filtering.

关键词： gravitational waves algorithms astrostatistics techniques

Some optimizations on detecting gravitational wave using convolutional neural network

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Frontiers of physics 2020年第5期15卷 65-75页

作者： xiang-Ru Li wo-Liang Yu Xi-Long Fan G.Jogesh Babu School of Computer Science South China Normal UniversityGuangzhou 510631China School of Mathematical Sciences South China Normal UniversityGuangzhou 510631China School of Physics and Technology Wuhan UniversityWuhan 430072China Pennsylvania State University University ParkPA 16802USA

This work investigates the problem of detecting gravitational wave(GW)events based on simulated damped sinusoid signals contaminated with white Gaussian *** is treated as a classifcation problem with one class for the interesting *** proposed scheme consists of the following two successive steps:decomposing the data using a wavelet packet,representing the GW signal and noise using the derived decomposition clficients;and determining the existence of any GW event using a convolutional neural network(CNN)with a logistic regression output *** characteristic of this work is its comprehensive investigations on CNN structure,detection window width,data resolution,wavelet packet decomposition and detection window overlap *** simulat ion experiments show excellent performances for reliable detection of signals with a range of GW model parameters and signal-to-noise *** we use a simple waveform model in this study,we expect the method to be particularly valuable when the potential GW shapes are too complex to be charncterized with a termplate bank.

关键词： gravitational waves algorithms astrostatistics techniques

Decentralized robust guaranteed cost control for a class of interconnected singular large-scale systems with time-delay and parameter uncertainty

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Journal of Systems Engineering and Electronics 2007年第1期18卷 111-119页

作者： wo Songlin Shi Guodong Zou Yun Division of Public Teaching Changzhou Coll. of Information Technology Changzhou 213164 P. R. China Dept. of Automation Nanjing Univ. of Science and Technology Nanjing 210094 P. R. China

The decentralized robust guaranteed cost control problem is studied for a class of interconnected singular large-scale systems with time-delay and norm-bounded time-invariant parameter uncertainty under a given quadratic cost performance function. The problem that is addressed in this study is to design a decentralized robust guaranteed cost state feedback controller such that the closed-loop system is not only regular, impulse-free and stable, but also guarantees an adequate level of performance for all admissible uncertainties. A sufficient condition for the existence of the decentralized robust guaranteed cost state feedback controllers is proposed in terms of a linear matrix inequality （LMI） via LMI approach. When this condition is feasible, the desired state feedback decentralized robust guaranteed cost controller gain matrices can be obtained. Finally, an illustrative example is provided to demonstrate the effectiveness of the proposed approach.

关键词： Uncertain singular large-scale systems Time-delay system Guaranteed cost control LMI

Rational Design of wo_3 Nanostructures as the Anode Materials for Lithium-Ion Batteries with Enhanced Electrochemical Performance

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Nano-Micro Letters 2015年第1期7卷 12-16页

作者： Yang Liu Yang Jiao Haiyue Zhou xiang Yu Fengyu Qu xiang Wu Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of Education and College of Chemistry and Chemical Engineering Harbin Normal University

A facile, one-step hydrothermal method was employed to synthesize two kinds of wo3 nanostructures. By using different kinds of sylvine, tungsten trioxide(wo3) with different morphologies of microflowers and nanowires was obtained, respectively. The discharge capacities for microflowers and nanowires are 107 and 146 m Ah g-1 after 180 cycles, and their corresponding capacity retentions after the first cycle are 72 and 85 %, respectively. Even at a high current density of 1,600 m Ah g-1, the discharge capacities of wo3 microflowers and nanowires are as high as 433 and557 m Ah g-1 after 40 cycles, in which the current densities were increased stepwise. It is worth mentioned that the rate capability of the nanowires is superior to that of the microflowers. However, the cycle performance of the microflowers is better than nanowires, revealing that the morphology and structure of the as-synthesized wo3 products can exert great influence on the electrochemical performances.

关键词： wo3 nanostructures Anode materials Li-ion batteries

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凸轮轴框架孔加工精度分析及变形工艺优化

内燃机与配件 2023年第18期 35-37页

作者：沃向东牛立梅陈文波李建青王昊刘继辉侯雅洁山西柴油机工业有限责任公司山西大同037036

凸轮轴框架是某型号柴油机中新设计的关键零件,采用沉降式并排结构孔,整体结构壁薄,形位公差要求严,加工过程中精度不易保证,影响柴油机性能。针对该型柴油机凸轮轴框架轴承孔加工过程中出现的平行度、同轴度、圆柱度超差及变形等问题... 详细信息

凸轮轴框架是某型号柴油机中新设计的关键零件,采用沉降式并排结构孔,整体结构壁薄,形位公差要求严,加工过程中精度不易保证,影响柴油机性能。针对该型柴油机凸轮轴框架轴承孔加工过程中出现的平行度、同轴度、圆柱度超差及变形等问题展开研究,并通过优化工艺方案、刀具方案,改进高效率线镗刀加工方法、订制配有自润滑系统,采用PLC控制液压转角缸的专用镗孔夹具等措施,减小工件变形,使夹紧力均匀可调,减少装夹时间,减小员工劳动强度,最终实现某型号柴油机凸轮轴框架轴承孔高精度加工及变形控制。

关键词：凸轮轴框架轴承孔加工精度变形工艺优化

Dechlorination mechanism of 2,4-dichlorophenol by Ni/Fe nanoparticles in the presence of humic acid

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 121-126页

作者： Jing-jing wo Zhen ZHANG Xin-hua XU Department of Environmental Engineering Zhejiang University Hangzhou 310027 China School of Bioscience Taizhou University Linhai 317000 China

To understand the feasibility of its application to the in situ remediation of contaminated groundwater,the dechlori-nation of 2,4-dichlorophenol (2,4-DCP) by Ni/Fe nanoparticles in the presence of humic acid (HA) was *** found that,as high performance liquid chromatography (HPLC) was used,the 2,4-DCP was first quickly reduced to o-chlorophenol (o-CP) and p-chlorophenol (p-CP),and then reduced to phenol as the final *** experimental results indicated that HA had an adverse effect on the dechlorination of 2,4-DCP by Ni/Fe nanoparticles,as the HA concentration increased,the removal rate decreased *** also demonstrated that 2,4-DCP was reduced more easily to o-CP than to p-CP,and that the sequence of the tendency in dechlorination of intermediates was p-CP>*** electron microscope (TEM) showed that HA could act as an adsorbate to compete reactive sites on the surface of Ni/Fe nanoparticles to decrease the dechlorination *** we con-cluded that the dechlorination reaction of 2,4-DCP over Ni/Fe nanoparticles progressed through catalytic reductive dechlorination.

关键词： Dechlorination Ni/Fe nanoparticles 2 4-dichlorophenol (2 4-DCP) Humic acid (HA)

Preliminary assessment of growth and survival of green alder(Alnus viridis), a potential biological stabilizer on fly ash disposal sites

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Journal of Forestry Research 2015年第1期26卷 131-136页

作者： Marcin Pietrzykowski wojciech Krzaklewski Bartomiej wo Department of Forest Ecology Forest FacultyUniversity of Agriculture in Krakow

This paper presents preliminary assessment of seedling survival and growth of green alder（Alnus viridis（Chaix） DC. in Lam. ＆ DC.） planted on fly ash disposal sites. This kind of post-industrial site is extremely hard to biologically stabilize without top-soiling. The experiment started with surface preparation using NPK start-up mineral fertilizer at 60–36–36 kg ha-1followed by initial stabilization through hydro-seeding with biosolids（sewage sludge 4 Mg ha-1dry mass） and a mixture of grasses（Dactylis glomerata L. and Lolium multiflorum Lam.）（200 kg ha-1）. Subsequently, three-years-old green alder seedlings were planted in plots on two substrate variants：the control（directly on combustion waste） and plots with3 dm3 lignite culm from a nearby mine introduced into the planting pit. Five years of preliminary monitoring show good survival seedling rates and growth parameters（height（h）, average increase in height（Dh）, number of shoots（L o）and leaf nitrogen supply in the fly ash disposal *** of the site with a combination of lignite culm in planting pits and preliminary surface preparation by hydroseeding and mineral fertilization had the most positive effect on green alder seedling parameters. The results indicate that it is possible and beneficial to use green alder for biological stabilization on fly ash disposal sites.

关键词： Fly ash Green alder Seedlings survival Growth Biological stabilisation

Kinetics of 2,4-dichlorophenol dechlorination by Pd-Fe bimetallic nanoparticles in the presence of humic acid

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 118-124页

作者： Zhen ZHANG Jing-jing wo Naman CISSOKO Xin-hua XU Department of Environmental Engineering Zhejiang University Hangzhou 310027 China School of Bioscience Taizhou University Linhai 317000 China

The remediation of groundwater which contains chlorinated organic compounds (COCs) by nanoscale bimetallic catalysts has received increasing interest in recent years. This report presents the dechlorination of 2,4-dichlorophenol (2,4-DCP) by Pd-Fe bimetallic nanoparticles in the presence of humic acid (HA) to investigate the feasibility of using Pd-Fe for the in situ remediation of contaminated groundwater. Our experimental results indicated that HA had an adverse effect on the dechlorination of 2,4-DCP by Pd-Fe nanoparticles. The rate constant k values of 2,4-DCP dechlorination were 0.017, 0.013, 0.009, 0.006 and 0.004 min?1 for HA concentrations of 0, 5, 10, 15 and 20 mg/L, respectively. The relationship between HA dosage and k values can be described as a linear model.

关键词： 2,4-dichlorophenol (2,4-DCP) Dechlorination Pd-Fe bimetallic nanoparticles Humic acid (HA)

Phylogenetic,Demographic and Dating Analyses of Bufo gargarizans Populations from the Zhoushan Archipelago and China's Mainland

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Asian Herpetological Research 2017年第3期18卷 165-173页

作者： Haojie TONG Yubin wo Pinghu LIAO Yuanting JIN College of Life Sciences China Jiliang University

Relatively little is known about the relationship between Bufo gargarizans populations from Zhoushan Archipelago and nearby continental regions on the Pacific coast of eastern *** this paper,155 new specimens of *** from Zhoushan Archipelago and adjacent continents and 71 published specimens of *** from China's Mainland were *** and dating analyses of *** were performed using mitochondrial DNA sequencing with a length of 1436 bp.A mt DNA tree that indicated seven major clades was *** earliest split in the mt DNA tree corresponding to the divergence of populations from the western highland region occurred approximately 4.0 million years ago（mya）.A subsequent clade occurred about 3.4 mya,with cladogenesis continuing toward the end of the *** continental clades were distributed in the western,central and northeastern regions of *** Archipelago clades consisted of two largely geographically overlapping subclades with the mt DNA divergence time of 0.73 *** results indicated there was extensive dispersal after *** *** populations on Zhoushan Archipelago most probably originated from populations in nearby eastern continental regions of *** was concluded that geological uplifting during the Pliocene and several sea-level changes in Pleistocene might have influenced the divergence and population demographical history of this species.

关键词： genetic structure island phylogeography mitochondrial DNA Bufo gargarizans