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Accurate recognition of the reproductive development status and prediction of oviposition fecundity in Spodoptera frugiperda(lepidoptera:Noctuidae)based on computer vision

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Journal of Integrative Agriculture 2023年第7期22卷 2173-2187页

作者： lÜChun-yang GE Shi-shuai HE Wei ZHANG hao-wen yANG Xian-ming CHU Bo WU Kong-ming Key laboratory of Agricultural Information Service Technology Ministry of Agriculture and Rural AffairsAgricultural Information InstituteChinese Academy of Agricultural SciencesBeijing 100081P.R.China State Key laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China State Key laboratory of Ecological Pest Control for Fujian and Taiwan Crops Institute of Applied EcologyFujian Agriculture and Forestry UniversityFuzhou 350002P.R.China College of Plant Protection Henan Agricultural UniversityZhengzhou 450002P.R.China

Spodoptera frugiperda(lepidoptera:Noctuidae)is an important migratory agricultural pest worldwide,which has invaded many countries in the Old World since 2016 and now poses a serious threat to world food *** present monitoring and early warning strategies for the fall army worm(FAW)mainly focus on adult population density,but lack an information technology platform for precisely forecasting the reproductive dynamics of the *** this study,to identify the developmental status of the adults,we first utilized female ovarian images to extract and screen five features combined with the support vector machine(SVM)classifier and employed male testes images to obtain the testis circular ***,we established models for the relationship between oviposition dynamics and the developmental time of adult reproductive organs using laboratory *** results show that the accuracy of female ovary development stage determination reached 91%.The mean standard error(MSE)between the actual and predicted values of the ovarian developmental time was 0.2431,and the mean error rate between the actual and predicted values of the daily oviposition quantity was 12.38%.The error rate for the recognition of testis diameter was 3.25%,and the predicted and actual values of the testis developmental time in males had an MSE of 0.7734.A WeChat applet for identifying the reproductive developmental state and predicting reproduction of *** was developed by integrating the above research results,and it is now available for use by anyone involved in plant *** study developed an automated method for accurately forecasting the reproductive dynamics of *** populations,which can be helpful for the construction of a population monitoring and early warning system for use by both professional experts and local people at the county level.

关键词： Spodoptera frugiperda computer vision ovary testis WeChat applet

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Design and synthesis of Fe-Ce-O@C with efficient photocatalytic activity

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Journal of Rare Earths 2023年第1期41卷 91-99页

作者： Zhonglian Xiao Xuanyi Wu Heyun Tan Shiyou hao Xingzhi College College of Chemistry and Life SciencesZhejiang Normal UniversityJinhua 321004China

Fe-Ce-OH@AR14 was obtained via the adsorption of acid red 14(AR14) on Fe-Ce-OH prepared by the codeposition of cerium nitrate hexahydrate,ferric nitrate nonahydrate,and ammonia,and then Fe-Ce-O@C with high photocatalyic efficiency was synthesized by the calcination of Fe-Ce-OH@AR14 in N_(2).For comparison,Fe-Ce-O was also prepared by the calcination of Fe-Ce-OH in N_(2).The obtained materials were characte rized by X-ray diffraction(XRD),Raman,X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FT-IR),scanning electron miscroscopy(SEM),photoluminescence(Pl),ultraviolet-visible diffuse reflectance spectroscopy(UV-vis) techniques and the results show that the band gap of CeO_(2) can be greatly reduced by doping of Fe^(3+),and that loading carbon from the decomposition of AR14 can prolong carrier life,improve the intensity of visible light absorption,and enhance the concentration of oxygen *** photocatalytic results using AR14 as probe molecule illustrate that using 1% ferric nitrate nonahydrate(the mass percentage of ferric nitrate nonahydrate to cerium nitrate hexahydrate) as dopant and 25 ml of 0.01 mmol/l AR14 as loading carbon resource is helpful for the photocatalytic efficiency of CeO_(2).

关键词： Fe-Ce-O@C Acid red 14 Carbon source Doping Photocatalysis Rare earths

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Theoretical and experimental investigation on novel 2D maglev servo proportional valve

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Chinese Journal of Aeronautics 2021年第4期34卷 416-431页

作者： Bin MENG hao XU Jian RUAN Sheng lI Key laboratory of Special Purpose Equipment and Advanced Manufacturing Technology Ministry of Education Zhejiang University of TechnologyHangzhou 310018China

This paper presents a novel two-dimensional maglev servo proportional cartridge valve(2 D maglev valve),where a contactless maglev coupling is introduced between electro-mechanical converter and valve body to realize functions of force transmission,spool position feedback and linear-rotary motion *** configuration can effectively reduce cost of both valve manufacturing and electro-mechanical converter,while still maintain features of 2 D valve such as null pilot leakage,high power-to-weight ratio and excellent anti-pollution ***,the characteristic equation of the valve is derived using linear theory,and the stability criterion is established for parameter *** influences of crucial structural parameters such as initial height of overlapping area,width of high-pressure and low-pressure holes,acting radius of magnetic force,pitch angle of maglev coupling,length of sensitive chamber and system pressure on the dynamic response are investigated based on AMESim numerical *** prototype valve is then designed and manufactured and a special test rig is *** no-load flow characteristic,load flow characteristic,leakage characteristic,amplitude and phase frequency characteristics and step response under different system pressures are *** experimental results are in a good agreement with the simulated *** an over-damped system,the prototype valve has excellent working stability,which can reach a no-load flow rate of 105.9 l/min with hysteresis of 3.51%,amplitude bandwidth of 28.7 Hz and phase bandwidth of 42.8 Hz under 21 *** research indicates that the 2 D maglev valve can be a potential solution of flow rate control valve for flight control surface system of civil aircraft with high pressure and large flow rate application.

关键词： Dynamic characteristic 2D valve Maglev coupling Servo proportional valve Stability criterion

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Cadmium-based metal-organic frameworks for high-performance electrochemical CO_(2) reduction to CO over wide potential range

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Chinese Journal of Chemical Engineering 2022年第3期35卷 143-151页

作者： Xin li Song Hong leiduan hao Zhenyu Sun State Key laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China College of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Electrochemical CO_(2)reduction(ECR)powered by renewable energy sources provides a sustainable avenue to producing carbon-neutral fuels and *** design and development of high performance,cost-effective,and stable catalysts for ECR remain a focus of intense ***,we report a novel electrocatalyst,two-dimensional cadmium-based 1,4-benzenedicarboxylate metal-organic frameworks(Cd-BDC MOFs)which can effectively convert CO_(2)to CO with a faradaic efficiency(FE)of more than80.0%over the voltage range between-0.9 and-1.1 V(versus reversible hydrogen electrode,***)in 0.1 mol·l^(-1) CO_(2)-saturated KHCO_(3)solution with an H-type cell,reaching up to 88.9%at-1.0 V(***).The performance outperforms commercial CdO and many other MOF-based materials demonstrated in prior *** catalytic property can be readily tuned by manipulating synthesis conditions as well as electrolyte ***,high CO FEs exceeding 90.0%can be attained on the Cd-BDC electrode at potentials ranging from-0.16 to-1.06 V(***)in 0.5 mol·l^(-1) KHCO_(3)solution by using a gas diffusion electrode cell *** maximum CO FE approaches~97.6%at-0.26 V(***)and the CO partial geometric current density is as high as about 108.1 mA·cm^(-2) at-1.1 V(***).This work offers an efficient,low cost,and alternative electrocatalyst for CO_(2)transformation.

关键词： Electrochemical carbon dioxide reduction Carbon monoxide Cadmium Metal-organic framework Electrocatalysis

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High-temperature oxidation resistance of ceramic coatings on titanium alloy by micro-arc oxidation in aluminate solution

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Progress in Natural Science:Materials International 2022年第4期32卷 401-406页

作者： Guodong hao Daiyue Zhang liyan lou longcheng yin Mudanjiang Normal University Harbin Institute of Technology

Ceramic coatings with aluminum titanuate(Al2TiO5) were prepared on Ti–6Al–4V alloy using pulsed bi-polar Micro-arc Oxidation(MAO). The micromorphology and phase composition of the micro-arc-oxidition ceramic coatings on the titanium alloy were characterized by X-ray powder diffraction(XRD), and scanning electron microscopy(SEM) respectively. The results revealed that the distinct discharge channels and pores on the surface of the micro-arc-oxidition coatings appeared, and these channels were connected in the molten state. The electrolyte concentration was inversely proportional to the coating hardness; additionally, the coating prepared with sodium aluminate and sodium hypophosphite concentrations of 4 g/l and 0.5 g/l, respectively, was the most refined after high-temperature sintering, and it was demonstrated to better prevent oxidation. Increasing the electrolyte concentration coincided with fluctuating coating thermal shock resistance. The thermal shock resistance of the coating respectively prepared with sodium aluminate, and the sodium hypophosphite concentrations of 4 g/l and 0.5 g/l was the highest. Additionally, the high-concentration coatings performed significantly better than the low-concentration coatings. The oxidation resistance of the coating samples was also significantly higher than that of the TC4 titanium alloy substrate. The adhesion strength between the coatings and the substrate with and without the sealing treatment was measured by tensile tests. Then, the high-temperature oxidation performance of the coating samples with and without the sealing treatment was investigated by conducting a hightemperature oxidation experiment at a calcinating temperature of 500°C. The results indicate that the adhesion strength between the coatings and substrate was high for the as-prepared and sealed micro-arc oxidation samples regardless of whether they were calcined. The high-temperature oxidation mass increase curves for the sealed and unsealed coating sampl

关键词： Micro-arc oxidation Titanium alloy Aluminate High-temperature oxidation Electrolyte concentration

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Preparation and properties of bifunctional Gd_(2)O_(3)/GQD composite nanoparticles

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Journal of Rare Earths 2022年第7期40卷 1118-1125页

作者： Chengjie Xu Meigui Ou hao Zhou Chunlin yang College of Materials and Metallurgy University of GuizhouGuiyang 550025China National local Co-construction Engineering laboratory for High Performance Metal Structure Material and Manufacture Technology Guiyang 550025China College of Chemistry and Materials Engineering Guiyang UniversityGuiyang 550003China

Nanocomposites of graphene quantum dots(GQDs)modified gadolinium oxide(Gd_(2)O_(3))particles were successfully *** addition,the effects of the amount of GQDs and the particle size of Gd_(2)O_(3)on the properties of nanocomposites were *** structures and properties of nanoparticles were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,Fourier transform infrared spectroscopy,field emission scanning electron microscopy,transmission electron microscopy,photoluminescence spectrometry,and magnetic resonance *** results show that the synthesized particles Gd_(2)O_(3)/GQD are spherical with a diameter of approximately 40 nm and have excellent fluorescence and magnetic property,and its relaxation rate(r_(1)=25.18(mmol/l)^(-1)/s)is higher than that of the typical commercial contrast agents Gd-DTPA(r_(1)=4.5(mmol/l)^(-1)/s),The fluorescence property of Gd_(2)O_(3)/GQD is optimized by varying the V_(GQDs):V_(Gd2O3)ratio,and 1:1 ratio of V_(GQDs):V_(Gd2O3)results in the best fluorescence *** large particles of Gd_(2)O_(3)improve the relaxation property of ***,the nanocomposites Gd_(2)O_(3)/GQD with magnetic and fluorescence characteristics can be used in biological imaging,drug targeting,and in-vivo diagnostic analysis.

关键词： Gd_(2)O_(3)/GQD Magnetic Fluorescence Magnetic resonance imaging(MRI) Rare earths

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An effective array beamforming scheme based on branch-and-bound algorithm

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Journal of Systems Engineering and Electronics 2023年第6期34卷 1483-1489页

作者： yE Xiaodong lI li WANG hao TAO Shifei School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjing 210094China

In this paper, we propose an effective full array and sparse array adaptive beamforming scheme that can be applied for multiple desired signals based on the branch-and-bound algorithm. Adaptive beamforming for the multiple desired signals is realized by the improved Capon method. At the same time,the sidelobe constraint is added to reduce the sidelobe level. To reduce the pointing errors of multiple desired signals, the array response phase of the desired signal is firstly optimized by using auxilary variables while keeping the response amplitude unchanged. The whole design is formulated as a convex optimization problem solved by the branch-and-bound algorithm. In addition,the beamformer weight vector is penalized with the modified reweighted l_(1)-norm to achieve sparsity. Theoretical analysis and simulation results show that the proposed algorithm has lower sidelobe level, higher SINR, and less pointing error than the stateof-the-art methods in the case of a single expected signal and multiple desired signals.

关键词： multiple desired signal auxiliary variable branchand-bound algorithm reweighted-norm.

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Theoretical investigation of loading Ni clusters on the α-Ga_2O_3 surfaces for photocatalytic hydrogen evolution

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Journal of Energy Chemistry 2019年第3期28卷 8-18页

作者： Jiaxin Zhang yidan Wang hao Dong Xin Zhou School of Chemistry and Chemical Engineering Liaoning Normal University College of Environment and Chemical Engineering Dalian University

In the semiconductor-based photocatalysts for overall water splitting, loading proper cocatalysts play a crucial role in enhancing the photocatalytic activity. In this work, we have chosen Ni_n/α-Ga_2O_3 as a model and provided detailed density functional theory calculations to investigate the function of cocatalysts in hydrogen evolution reaction(HER). We have studied the formation and stability of Ni_n(n = 1–4) cluster on two stable surfaces of α-Ga_2O_3(001) and(012). In a Ni_n/α-Ga_2O_3 system, as the Ni 3d states well overlap with O and Ga states, the excited electrons transferred from Ga to Ni may participate in HER. We theoretically predict that introduction of Nincluster on(012) surface can elevate the Fermi level toward the conduction band, which is favorable for the occurrence of HER. Electrochemical computations are used to explore the mechanism of HER. It is found that, in most of Ni_n/α-Ga_2O_3 systems, the active sites of HER are on Ni_n clusters. loading Ni_n clusters not only importantly reduces the Gibbs free energy of HER but also improves the reaction activity of surface O and Ga sites in HER. Our calculations reasonably explain the experimental observation on significant enhancement of activity for generating hydrogen after loading nickel oxide cocatalysts.

关键词： Photocatalytic hydrogen evolution reaction Cocatalysts Electronic structure calculation Density functional theory Ga2O3

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Synthesis of pyrrolidinyl-ethylene fluorenyl rare-earth metal complexes and catalysis for 2-vinylpyridine polymerization

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Journal of Rare Earths 2023年第3期41卷 381-387,I0003页

作者： yinjun Wang hao Jiang Huifei Wang Zehuai Mou Key laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province School of Material Science and Chemical EngineeringNingbo UniversityNingbo 315211China

The metathesis reaction between pyrrolidinyl-ethylene fluorenyl lithium salts with in situ prepared cationic rare-earth metal dialkyl species[ln(CH_(2)SiMe_(3))_(2)(THF)_(x)][BPh_(4)]afford efficiently the corresponding constrained-geometry complexes l^(1)ln(CH_(2)SiMe_(3))_(2)(l^(1)=FluCH_(2)CH_(2)NC_(4)H_(8),ln=y(1a),lu(1b),Sc(1c))and l^(2)ln(CH_(2)SiMe_(3))_(2)(l^(2)=(2,7-di-tert-butyl)FluCH_(2)CH_(2)NC_(4)H_(8),ln=y(2a),lu(2b),Sc(2c))in good *** these complexes were characterized by NMR spectroscopy,and the solid-state molecular structure of yttrium complex 1a was defined with single-crystal X-ray diffraction *** catalytic performance of these complexes towards 2-vinylpyridine polymerization was investigated,where these complexes alone can efficiently promote the polymerization of 2-vinylpyridine giving isotactic poly(2-vinylpyridine).Upon the activation with[Ph_(3)C][B(C_(6)F_(5))_(4)],the yttrium and lutetium complexes also afford isotactic poly(2-vinylpyridine),while the scandium complexes produce syndiotactic poly(2-vinylpyridine).

关键词： Rare-earth metal Constrained-geometry complex 2-Vinylpyridine Stereoselective polymerization

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Enhancement of spike coherence by the departure from Gaussian noise in a Hodgkin-Huxley neuron

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Science China Chemistry 2009年第8期52卷 1186-1191页

作者： XIE yanHang GONG yuBing hao yingHang School of Physics&Electronic Engineering Ludong UniversityYantai 264025China

Experimental study has shown that non-Gaussian noise exists in sensory systems like *** departure from Gaussian behavior is a characteristic parameter of non-Gaussian *** this paper,we have numerically studied the effect of a particular kind of non-Gaussian colored noise(NGN),especially its departure q from Gaussian noise(q = 1),on the spiking activity in a deterministic Hodgkin-Huxley(HH) neuron driven by sub-threshold periodic *** results show that the departure q can affect the spiking activity induced by noise intensity *** smaller q values,the minimum in the variation coefficient(CV) as a function of noise intensity(D) becomes smaller,showing that D-induced stochastic resonance(SR) becomes ***,depending on the value of D,q can either enhance or reduce the spiking ***,CV changes non-monotonously with varying q and passes through a minimum at an intermediate q,representing the presence of "departure-induced SR".This result shows that appropriate departures of the NGN can enhance the spike coherence in the HH *** the departure of the NGN determines the probability distribution and hence may denote the type of the noise,"departure-induced SR" shows that different types of noise can enhance the spike coherence,and hence may improve the timing precision of sub-threshold signal encoding in the HH neuron.

关键词： neuron non-Gaussian colored noise spike coherence stochastic resonance stochastic dynamics

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