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Underwater acoustic signal denoising model based on secondary variational mode decomposition

Defence Technology（防务技术） 2023年第10期28卷 87-110页

作者： Hong Yang Wen-shuai Shi guo-hui li School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'anShaanxi710121China

Due to the complexity of marine environment,underwater acoustic signal will be affected by complex background noise during *** acoustic signal denoising is always a difficult problem in underwater acoustic signal *** obtain a better denoising effect,a new denoising method of underwater acoustic signal based on optimized variational mode decomposition by black widow optimization algorithm(BVMD),fluctuation-based dispersion entropy threshold improved by Otsu method(OFDE),cosine similarity stationary threshold(CSST),BVMD,fluctuation-based dispersion entropy(FDE),named BVMD-OFDE-CSST-BVMD-FDE,is *** the first place,decompose the original signal into a series of intrinsic mode functions(IMFs)by ***,distinguish pure IMFs,mixed IMFs and noise IMFs by OFDE and CSST,and reconstruct pure IMFs and mixed IMFs to obtain primary denoised *** the end,decompose primary denoising signal into IMFs by BVMD again,use the FDE value to distinguish noise IMFs and pure IMFs,and reconstruct pure IMFs to obtain the final denoised *** proposed mothod has three advantages:(i)BVMD can adaptively select the decomposition layer and penalty factor of VMD.(ii)FDE and CS are used as double criteria to distinguish noise IMFs from useful IMFs,and Otsu algorithm and CSST algorithm can effectively avoid the error caused by manually selecting thresholds.(iii)Secondary decomposition can make up for the deficiency of primary decomposition and further remove a small amount of *** chaotic signal and real ship signal are *** experiment result shows that the proposed method can effectively *** improves the denoising effect after primary decomposition,and has good practical value.

关键词： Underwater acoustic signal Denoising Variational mode decomposition Secondary decomposition Fluctuation-based dispersion entropy Cosine similarity

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A novel feature extraction method for ship-radiated noise

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Defence Technology（防务技术） 2022年第4期18卷 604-617页

作者： Hong Yang Lu-lu li guo-hui li Qian-ru Guan School of Electronic Engineering Xi’an University of Posts and TelecommunicationsXi’anShaanxi710121China

To improve the feature extraction of ship-radiated noise in a complex ocean environment,a novel feature extraction method for ship-radiated noise based on complete ensemble empirical mode decomposition with adaptive selective noise(CEEMDASN) and refined composite multiscale fluctuation-based dispersion entropy(RCMFDE) is *** is proposed in this paper which takes into account the high frequency intermittent components when decomposing the *** addition,RCMFDE is also proposed in this paper which refines the preprocessing process of the original signal based on composite multi-scale ***,the original signal is decomposed into several intrinsic mode functions(IMFs)by *** distribution ratio(EDR) and average energy distribution ratio(AEDR) of all IMF components are ***,the IMF with the minimum difference between EDR and AEDR(MEDR)is selected as characteristic *** RCMFDE of characteristic IMF is estimated as the feature vectors of ship-radiated ***,these feature vectors are sent to self-organizing map(SOM) for classifying and *** proposed method is applied to the feature extraction of ship-radiated *** result shows its effectiveness and universality.

关键词： Complete ensemble empirical mode decomposition with adaptive noise Ship-radiated noise Feature extraction Classification and recognition

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Molecular Characterization of Three Ethylene Responsive Element Binding Factor Genes from Cotton

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Journal of Integrative Plant Biology 2010年第5期52卷 485-495页

作者： Long-guo Jin hui li Jin-Yuan liu Laboratory of Molecular Biology and MOE Laboratory of Protein Science Department of Biological Sciences and Biotechnology TsinghuaUniversity Beijinq 100084 China

Ethylene-responsive factors （ERFs） are important regulators of plant gene expression. In this study, three novel ERF genes, GhERF2, GhERF3 and GhERF6, were isolated from cotton （Gossypium hirstum） using rapid amplification of cDNA ends-polymerase chain reaction. Transient expression analysis using GhERF-green fluorescent protein fusions showed that these three proteins were targeted to the nucleus. Fusion proteins consisting of GhERF2, GhERF3 or GhERF6 coupled to the GAL4 DNA binding domain strongly activated transcription in yeast. Furthermore, GhERF6 was shown to be able to bind specifically to GCC boxes using a particle bombardment assay in tobacco cells. Semi-quantitative reverse transcription-polymerase chain reaction revealed that GhERF2 and GhERF3 are constitutively expressed in all organs, while GhERF6 is only constitutively expressed in vegetative organs. When plants were treated with ethylene, abscisic acid, salt, cold and drought, the transcripts of GhERF2, GhERF3 and GhERF6 were rapidly induced to high levels. Promoter analysis also indicated that the 5＇ upstream regions of the three genes possess elements induced by these physiological and environmental factors. Collectively, our data suggest that GhERF2, GhERF3 and GhERF6 might function as positive trans-acting factors in the plant responses to ethylene, abscisic acid and other stresses and provide useful clues for further research into the mechanism of them in regulating cotton multiple stress responses.

关键词： Ethylene Cotton Gossypium Regulations Plants Planting Uses Genes ABA Lymphocytes

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In situ anchoring in carbon matrix of Bi_(2)O_(2)CO_(3) as a high-performance anode material for li-ion batteries

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Rare Metals 2024年第8期43卷 3634-3646页

作者： Pu-Qiang He Jun guo hui Huang Zhong-Cheng guo Faculty of Metallurgy and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Research Center of Metallurgical Electrode Materials Engineering Technology Kunming 650106China Kunming Hendera Science and Technology Co. Ltd.Kunming 650106China

Bismuth-based anode materials have been regarded as promising li-ion batteries due to their high theoretical ***,their low conductivity and associated volume expansion inhabited their *** this work,Bi_(2)O_(2)CO_(3)@C composites were successfully synthesized by in situ anchoring of flower-like Bi_(2)O_(2)CO_(3) nanosheets on a carbon-based substrate via *** unique composited structure of Bi_2O_(2)-CO_(3)@C leads to a stable specific capacity of 547 mAh·g^(-1)after 100 cycles at a current density of 0.1 A·g^(-1).Notably,it demonstrates excellent rate capability with a specific capacity of 210 mAh·g^(-1)at 5 A·g^(-1).After 550 cycles at a current density of 0.5 A·g^(-1),a high reversible capacity of nearly 400 mAh·g^(-1)was ***,in situ X-ray diffraction measurements clearly demonstrate the conversion between Bi and li_(3)Bi during alloying/dealloying,confirming the good electrochemical reversibility of the materials for li *** reaction kinetics of Bi_(2)O_(2)CO_(3)@C were further investigated using galvanostatic intermittent titration ***,Bi_2O_(2)-CO_(3)@C exhibited excellent long-term stability,maintaining its high reversible capacity for over 200 cycles at a current density of 0.5 A·g^(-1)in a full cell configuration using li_(1.20)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2) as the cathode *** result further underscores its promising potential for lithium-ion *** work may provide inspiration for the design of alloy-type negative electrode materials for high-performance rechargeable batteries.

关键词： Bi_(2)O_(2)CO_(3) Composite materials Anode materials Full batteries

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Haplotypes at the 5′-Flanking Region of Peroxisome Proliferator-Activated Receptor γ Gene and Their Association with the Growth and Body Composition Traits in Chickens

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Agricultural Sciences in China 2011年第2期10卷 296-303页

作者： HAN Qing WANG Shou-zhi HU guo li hui College of Animal Science and Technology Northeast Agricultural UniversityHarbin 150030P.R.China

Peroxisome proliferator-activated receptor g（PPARg） is an important regulator of chicken preadipocyte proliferation and *** this study,polymorphisms were detected by DNA sequencing,PCR-RFLP and some other methods and three polymorphisms（g.-1784_-1768del17,c.-1241GA and c.-75GA） were found in the 5＇ flanking region of PPARg *** and body composition traits were measured in the 8th-10th generation populations of the Northeast Agricultural University broiler lines were divergently selected for abdominal fat *** among individuals were screened in the above *** haplotype-based association analysis on growth and body composition traits was carried *** association analysis showed that haplotypes based on three polymorphisms at 5＇ flanking region of PPARg gene were significantly associated with abdominal fat weight（AFW）,abdominal fat percentage（AFP,AFW/BW7）,liver weight（LW）,liver weight percentage（LFP,LW/BW7）,shank length（ShL）,femur weight（FeW）,keel length（KeL）,and metatarsus circle（MeC）（P0.05） and suggestive significantly associated with pectoralis major weight（PMaW）,pectoralis minor weight（PMiW）,pectoralis minor weight percentage（PMiWP,PMiW/BW7）,and metatarsus length（MeL）（P0.2）.The least square analysis showed that the birds with BGA haplotype had significantly higher AFW and AFP than the birds with other haplotypes（P0.05）.The birds with AAG haplotype had significantly higher LW and LW/BW than the birds with other haplotypes（P0.05）.The birds with AAG haplotype had significantly higher PMiW and PMiW/BW than the birds with other haplotypes（P0.05）.The birds with AAG haplotype had significantly higher ShL,FeW,MeL,MeC and KeL than the birds with AGG haplotypes（P0.05）.The results in this study revealed that QTL affecting fatness traits may exist in 5＇ flanking region of PPARg gene in chickens and PPARg gene might be one of the genes having important influences on the growth and bone traits in chickens.

关键词： chicken PPARg haplotype fatness bone major gene

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Ace2, rather than ace1, is the major acetylcholinesterase in the silkworm, Bombyx moil

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Insect Science 2009年第4期16卷 297-303页

作者： hui-Juan Chen Zhen liao Xiao-Ming hui guo-Qing li Fei li Zhao-Jun Han Department of Entomology Nanjing Agricultural University Nanjing China

Two acetylcholinesterase （ace） genes have been reported in many insect species. In pests such as Helicoverpa assulta and Plutella xylostellas, acel gene encodes the predominant synaptic enzyme that is the main target of organophosphorus （OP） and carbamate pesticides. It has been reported that pesticide selection has an impact on the ace gene evolution. The domesticated silkworm, Bombyx mori, also has two ace genes. We studied ace gene expression and enzyme activities in silkworm as this has not faced pesticide selection over the past decades. The expression levels of two ace genes, Bm-acel and Bm-ace2, were estimated by quantitative real-time polymerase chain reaction. Bin-ace2 was expressed more highly than Bm-acel in all tested samples of different developmental stages or tissues, suggesting ace2, rather than acel, is the major type ofacetylcholinesterase （ACHE） in Bombyx mori. This is inconsistent with the aforementioned lepidopterons agricultural pests, partly be due to the widespread use of pesticides that may induce high expression of the acel gene in these pests. Besides high expression in the head, Bm-acel also expresses highly in the silk glands and Bm-ace2 is abundant in the germline, implying both ace genes may have potential non-hydrolytic roles in development. Furthermore, we found that the mRNA levels of two ace genes and their ratios （ace2/acel） change day to day in the first and third instars. This challenges the conventional method of estimating enzymatic activity using crude extract as an enzyme solution, as it is a mixture of ACHE 1 and ACHE2. An efficient and simple method for separating different ACHEs is necessary for reliable toxicological analyses.

关键词： acetylcholinesterase Bombyx mori expression Kin quantitative real-time polymerase chain reaction (qRT-PCR)

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纳米铝粉在炸药中的应用研究进展及趋势

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爆破 2024年第1期41卷 159-171页

作者：郭惠丽张为鹏黄亚峰赵东奎西安近代化学研究所陕西710065

铝粉是火炸药行业中最常用的金属燃料。相比微米铝粉,纳米铝粉的比表面积、反应活性和反应完全性都高得多。因此,将纳米铝粉应用于炸药中,无疑将改善炸药的反应完全性,增加炸药威力,提高弹药的毁伤效能。本文系统综述了纳米铝粉对爆轰... 详细信息

铝粉是火炸药行业中最常用的金属燃料。相比微米铝粉,纳米铝粉的比表面积、反应活性和反应完全性都高得多。因此,将纳米铝粉应用于炸药中,无疑将改善炸药的反应完全性,增加炸药威力,提高弹药的毁伤效能。本文系统综述了纳米铝粉对爆轰性能、安全性能、工艺性能等多种炸药性能的影响。就爆轰性能而言,纳米铝粉可以提高混合炸药几乎所有的爆轰参数,包括爆速、爆热、空中爆炸的冲击波超压峰值、水下爆炸的总能量、燃料空气炸药的爆炸压力峰值和爆炸压力上升速率、金属加速能力、纵火能力、作功能力及猛度等,可以全方位提高混合炸药的毁伤效果。但是,由于部分研究者选用的纳米铝粉有效铝含量差异较大,常常得出不同的结论。就安全性能而言,纳米铝粉的引入提高了混合炸药的撞击感度、摩擦感度、冲击波感度、热感度等,显著降低了炸药的点火能,并且对常用炸药(如TNT、RDX、HMX、CL-20、NG、TATB等)热分解有促进作用,导致纳米炸药的引入对混合炸药的安全性能有不利影响;就工艺性能而言,在浇注固体炸药体系中,纳米铝粉增加了浇注固体炸药体系的粘度,降低了压装炸药体系中炸药药柱的密度,纳米炸药的引入恶化了混合炸药的工艺性能。本文指出,由于纳米铝粉的比表面积大、反应活性高,从制备到储存的各个环节极易氧化,造成纳米铝粉的有效铝含量急剧降低,是部分研究者得到错误结论的一个重要原因。因此,应深入研究纳米铝粉的制备方法和存储条件,使纳米铝粉在炸药中充分发挥效能。

关键词：金属材料金属纳米粒子火炸药

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Electrochemical properties of M1Ni_(3.5)Co_(0.6)Mn_(0.4)Al_(0.5)–x wt%Mm_(0.89)Mg_(0.11)Ni_(2.97)Mn_(0.14)Al_(0.20)Co_(0.54)composites

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Rare Metals 2015年第5期34卷 338-343页

作者： Hong-Xia Huang guo-hui li Xin-Ying Wang Yin li Xing Teng Ting Qi Guangxi Scientific Experiment Center of Mining Metallurgy and Environment College of Chemistry and BioengineeringGuilin University of Technology

In order to improve the overall electrochemical properties of ABs-type storage alloys, the new type composite alloys M1Ni3.5Co0.6Mn0.4Al0.5-x wt% Mm0.89Mg0.11Ni2.97Mn0.14Al0.20Co0.54 （x = 0, 5, 10; M1 means mischmetal） were prepared by means of ball milling. The composite alloys are shown to be single LaNi5 phase by X-ray diffraction （XRD） patterns. The maximum discharge capacity slightly increases from 315 mAh·g^-1 for M1Ni3.5Co0.6Mn0.4Al0.5 to 324 mAh·g^-1 （x = 5） and 325 mAh·g^-1 （x = 10）. The addition of AB3-type La-Mg- Ni-based alloy has a positive effect on the cycle stability. With the addition of Mm0.89Mg0.11Ni2.97Mn0.14-Al0.20Co0.54 alloy, the exchange current density （I0）, the limiting current density （IL） and the diffusion coefficient of hydrogen （D） of the alloy electrodes increase, leading to a corresponding improvement of the high rate dischargeability.

关键词： La-Mg-Ni-based alloy Composite alloys Electrochemical property Kinetics

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Synthesis and characterization of non-symmetrical liquid crystals containing a cholesteryl ester moiety

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Chinese Chemical Letters 2009年第5期20卷 562-565页

作者： Duo Wei Zhang Wei Huang guo hui Pan Wan li He Yu Bo Cao Jin Bao guo hui Cao Huai Yang Department of Materials Physics and Chemistry School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

In this paper, a series of chiral non-symmetrical liquid crystals （nBA-chol） consisting of a cholesteryl ester moiety as chiral entity and a biphenyl aromatic core with different terminal alkyl chain has been synthesized and investigated for their liquid crystalline properties. Effects of numbers of methylene units in the terminal alkyl chain on the phase transition temperatures and on the temperature-dependent pitch lengths of the chiral liquid crystals have been studied. The long terminal alkyl chain tends to exhibit smectic A mesophases. The pitch lengths of the cholesteric mesophases of the chiral liquid crystals decrease with increasing temperature and with increasing numbers of methylene units in the terminal alkyl chain, respectively.

关键词： liquid crystals Non-symmetrical Chiral Mesophase Pitch

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Layered niobium carbide enabling excellent kinetics and cycling stability of li-Mg-B-H hydrogen storage material Layered niobium carbide enabling excellent kinetics

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Rare Metals 2024年第3期43卷 1153-1166页

作者： li-Wen Lu hui Luo Guang-Xu li Yun li Xin-Hua Wang Cun-Ke Huang Zhi-QiangLan Wen-Zheng Zhou Jin guo Mohammad Ismail Hai-Zhen liu Guangxi Novel Battery Materials Research Center of Engineering Technology Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China State Key Laboratory of Featured Metal Materials and life-Cycle Safety for Composite Structures Nanning530004China School of Mechanical and Electrical Engineering Quzhou College of TechnologyQuzhou324000China Department of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia Terengganu21030Kuala NerusTerengganuMalaysia Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin300071China

The li-Mg-B-H composite(2liBH_(4)+MgH_(2))has a high capacity of 11.4 wt%as a hydrogen storage ***,the slow kinetics and poor cycling stability severely restrict its practical *** this work,a layered Nb_(2)C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the li-Mg-B-H *** milled 2liH+MgB_(2)composites were initially hydrogenated to obtain the 2liBH_(4)+MgH_(2)*** 2liBH_(4)+MgH_(2)+5wt%Nb_(2)C can release 9.0 wt%H_(2)in 30 min at 400℃,while it is only 2.7 wt%for the undoped 2liBH_(4)+MgH_(2).The dehydrogenation activation energies of MgH_(2)and liBH_(4)are 123 and 154 kJ·mol^(-1)respectively for the 5 wt%Nb_(2)C-doped composite,lower than the undoped composite(164 and 165 kJ·mol^(-1)).The 2liBH_(4)+MgH_(2)+5 wt%Nb_(2)C possesses excellent cycling stability,with the reversible capacity only slightly reduced from 9.4 wt%for the 1st cycle to 9.3 wt%for the 20th ***_(2)C keeps stable in the composite and acts as an efficient catalyst for the li-Mg-B-H *** is believed that both the layered structure and the active Nb element contribu te to the enhanced hydrogen storage performances of the li-Mg-B-H *** work confirms that the Nb_(2)C MXene with layered stru cture has a significant enhancing impact on the li-Mg-B-H hydrogen storage materials,which is different from the bulk NbC.

关键词： Hydrogen storage lithium borohydride Magnesium hydride Nb_(2)C MXene

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