检索结果-南通市图书馆

An introductory review on the common brown leafhopper(Orosius orientalis):A new soybean pest

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Oil Crop Science 2024年第3期9卷 198-203页

作者： Tianhao pei xin Cui Shusen Shi Yu Gao College of Plant Protection Jilin Agricultural UniversityChangchun130118PR China Key Laboratory of Soybean Disease and Pest Control Ministry of Agriculture and Rural AffairsChangchun130118PR China

Soybean pests are one of the major factors limiting yield *** the expansion of area and changes in cropping patterns,a number of new pests have been identified in the main soybean production areas of *** common brown leafhopper,Orosius orientalis,is a new pest associated with soybean stay-green virus that has been discovered on cultivated soybean crop in the Yellow-Huai-hai region of China in recent *** polyphagous insect has a wide feeding range and infests a variety of important grain and cash *** paper presents the basic information,geographical distribution,hosts,damage characteristics,plant virus transmission,occurrence patterns,and prevention and control measures *** review also provides insights into integrated prevention and control of the genus Orosius as an insect vector.

关键词： Soybean Leafhopper Plant virus Insect vector Orosius orientalis

Uniform Truncation Error for Shannon Sampling Expansion from Local Averages

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2015年第1期31卷 121-130页

作者： Zhan-jie SONG pei-xin YE Ping WANG Shou-zhen ZENG School of Science and SKL of HESS Tianjin University School of Mathematics and LPMC Nankai University Department of Mathematics School of Science Tianjin University Institute of Mathmatics Zhejiang Wanli University

Let B^pΩ,1≤Р≤∞,be the set of all bounded functions in L^p（R）which can be extended to entire unctions of exponential typeΩ. The unitbrm bounds for truncation error of Shannon sampling expansion fromlocal averages are obtained for functions f∈BpΩwith the decay condition f（t）≤A/t^δ,t≠0,where A and δare positive constants. Furthermore we also establish similar results for non-bandlimit functions in Besov classes with the same decay condition as above.

关键词： Shannon sampling Theorem local averages truncation error modulus of continuity

Hydrogen storage properties of ball-milled Mg-based composite with PdCl_2 additive

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1510-1513页

作者： WANG Xiu-li TU Jiang-ping ZHANG pei-long ZHAO xin-bing Department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Mg-25 wt% Mg2Ni composite was prepared by sintered method, hydrided at 613 K and then ball-milled with 1.5 wt% PdC12 additive for 51 h. The effects of PdCl2 on the hydriding and dehydriding behavior of Mg-25 wt% Mg2Ni composite were investigated. The absorption and desorption rate of the composite with PdCl2 is fast and the hydrogen storage capacity is more than that of the composite without PdCl2. The maximum hydrogen storage capacity reached 3.48 wt% at 373 K, and 5.05 wt% H at 453 K, respectively. The improvement of sorption and desorption kinetics is attributed to the catalytic effect of PdCl2, and the grain refining and lattice strain introduced by ball milling.

关键词： Hydrogen storage Mg-based composite PdCl2 additive Ball milling

Conditional Random Field Tracking Model Based on a Visual Long Short Term Memory Network

在线全文

学校读者我要写书评

暂无评论

Journal of Electronic Science and Technology 2020年第4期18卷 308-319页

作者： pei-xin Liu Zhao-Sheng Zhu Xiao-Feng Ye Xiao-Feng Li School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731

In dense pedestrian tracking,frequent object occlusions and close distances between objects cause difficulty when accurately estimating object *** this study,a conditional random field tracking model is established by using a visual long short term memory network in the three-dimensional(3D)space and the motion estimations jointly performed on object trajectory *** visual field information is added to the long short term memory network to improve the accuracy of the motion related object pair selection and motion *** address the uncertainty of the length and interval of trajectory segments,a multimode long short term memory network is proposed for the object motion *** tracking performance is evaluated using the PETS2009 *** experimental results show that the proposed method achieves better performance than the tracking methods based on the independent motion estimation.

关键词： Conditional random field(CRF) long short term memory network(LSTM) motion estimation multiple object tracking(MOT)

Cyclic oxidation behavior of Ni_(3)Al-based single crystal alloy IC21

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2023年第5期42卷 1656-1662页

作者： Tian-Tian Yang xin Zhou Shu-Suo Li Yan-Ling pei Sheng-Kai Gong School of Materials Science and Engineering Beihang UniversityBeijing100191China

In this study,the cyclic oxidation tests of the Ni3Al-based single-crystal super alloy IC21 were carried out at 800,900,950,1000,1050 and 1100℃in *** present study shows that the complex oxide scale on the surface of the alloy is made up of an outer columnar NiO layer,an intermediate mixture of NiO and NiAl2O4layer with a small amount of Mo oxides and an inner continuous layer ofα-Al_(2)O_(3).The cyclic oxidation kinetics curves show that oxidation resistance at 800,900,950,1000 and1050℃seems to follow a similar law and is better than that at 1100℃.The overall weight changes at 1100℃follows a parabolic *** and severe rumpling of the oxide scale are observed on the surface of the alloy at1100℃,revealing the occurrence of disastrous oxidation.

关键词： Ni_(3)Al Thermal cycling Oxidation Microstructure

Solid-state reaction of a CaO−V_(2)O_(5)mixture:A fundamental study for the vanadium extraction process

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2021年第9期28卷 1462-1468页

作者： Jun-yi Xiang xin Wang Gui-shang pei Qing-yun Huang Xue-wei Lv College of Materials Science and Engineering Chongqing UniversityChongqing 400044China School of Metallurgy and Materials Engineering Chongqing University of Science and TechnologyChongqing 401331China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and Advanced Materials Chongqing UniversityChongqing 400044China

The aim of this study was to investigate the phase transformation and kinetics of the solid-state reaction of CaO−V_(2)O_(5),which is the predominant binary mixture involved in the vanadium recovery *** analysis,X-ray diffraction spectroscopy,scanning electron microscopy,and energy dispersive spectrometry were used to characterize the solid-state reaction of the *** extent of the solid reac-tion was derived using the preliminary quantitative phase analysis of the X-ray *** results indicate that the solid reaction of the CaO−V_(2)O_(5)mixture is strongly influenced by the reaction temperature and CaO/V_(2)O_(5)mole *** transformation of calcium vanadate in-volves a step-by-step reaction of CaO−V_(2)O_(5),CaO−CaV_(2)O_(6),and CaO−Ca_(2)V_(2)O7 depending on the CaO/V_(2)O_(5)mole *** kinetic data of the solid reaction of the CaO−V_(2)O_(5)(1:1)mixture followed a second-order reaction *** activation energy(Ea)and preexponential factor(A)were determined to be 145.38 kJ/mol,and 3.67×10^(8)min^(−1),respectively.

关键词： calcium vanadate vanadium extraction solid-state reaction kinetics

Development of Pulsar Digital Backend Based on RFSoC

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2022年第2期22卷 16-28页

作者： Toktonur Ergesh Jian Li Xue-Feng Duan xin pei Zhi-Gang Wen xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

Radio Frequency System on Chip(RFSo C)offers great potential for implementing a complete next generation signal processing system on a single board for radio *** designed a pulsar digital backend system based on the ZCU111 *** system uses RFSo C technology to implement digitization,channelization,correlation and high-speed data transmission in the Xilinx ZU28 DR *** have evaluated the performance of the eight 12-bit RF-ADCs,which are integrated in RFSo C,with the maximum sampling rate of 4.096 *** RF-ADC sampling frequency,channel bandwidth and time resolution can be configured dynamically in our designed *** verify the system performance,we deployed the RFSo C board on the Nanshan 26 m radio telescope and observed the pulsar signal with a frequency resolution of 1 MHz and time resolution of 64μ*** the observation test,we obtained pulsar profiles with high signal-to-noise ratio and accurately searched the DM *** experimental results show that the performance of RF-ADCs,FPGA and CPU cores in RFSo C is sufficient for radio astronomy signal processing applications.

关键词： astronomical instrumentation astronomical techniques radio astronomy

Metal-organic frameworks as photocatalysts for aerobic oxidation reactions

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2023年第6期66卷 1634-1653页

作者： Kun Wu xin-Yi Liu pei-Wen Cheng Mo Xie Weigang Lu Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsJinan UniversityGuangzhou 510632China

Metal-organic frameworks(MOFs)are emerging as one of the most intriguing classes of heterogeneous photocatalysts owing to their abundant structures,tunable porosity,and versatile *** advantages of bottom-up design and reticular synthesis render MOF materials with desired photocatalytic properties for targeted *** this review,we discussed the design and synthesis of MOF-based photocatalysts as well as strategies for enhancing photocatalytic *** progress on MOFs as platforms for photocatalytic aerobic oxidation reactions was summarized and categorized according to the types of bond *** hope this review will give an in-depth insight into MOF-based photocatalytic systems for not only aerobic oxidation reactions but also other organic transformations.A brief outlook on the challenges and opportunities of MOFs as heterogeneous photocatalysts is provided at the end of the review.

关键词： metal-organic frameworks heterogeneous photocatalyst reactive oxygen species aerobic oxidation organic synthesis

Salt freezing resistance improvement of cement-based materials incorporated with calcined layered double hydroxide

在线全文

学校读者我要写书评

暂无评论

Journal of Traffic and Transportation Engineering(English Edition) 2023年第3期10卷 427-440页

作者： Jinyang Huo Tonghuan Zhang Zhenjun Wang Xiaofeng Wang xin Ji pei Wang School of Materials Science and Engineering Chang'an UniversityXi'an 710064China Engineering Research Center of Transportation Materials of Ministry of Education Chang'an UniversityXi'an 710064China Henan Communications Planning&Design Institute Co. Ltd.Zhengzhou 450052China

Salt freezing damage has severe impacts on durability of cement-based materials(CBMs).Calcined layered double hydroxide(CLDH),as an efficient environmental-friendly adsorption material,can impart excellent salt freezing resistance to *** this work,salt freezing resistance improvement of CBMs incorporated with CLDH was experimentally evaluated by chloride binding capacity,mass loss rate,relative dynamic elastic modulus,setting time,compressive strength,and micro structure *** these,the salt freezing damage model was established to effectively express the quantitative relationship between influencing factors and evaluation indexes of the salt freezing resistance of *** show that CLDH can reconstruct its original layered structure to form reconstructed layered double hydroxide(RLDH).RLDH combines with chloride ions to form RLDH-Cl recrystallization,which can improve chloride binding capacity and pore structures of CBMs to relieve the salt freezing *** salt freezing damage model indicates that the suitable CLDH content can evidently alleviate the salt freezing damage,which facilitates the quantitative analysis of the effect of CLDH on the salt freezing resistance of CBMs.

关键词： Cement-based materials Calcined layered double hydroxide Salt freezing resistance Micro structure Salt freezing damage