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Synthesis,structural characterization and properties of a 3D infinitely extended structural rare earth coordination compound of K_3{[Sm(H_2O)_7]_2Na[α-SiW_(11)O_(39)Sm(H_2O)_4]_2}·14 H_2O

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Science China Chemistry 2005年第4期48卷 343-351页

作者： WANG Jingping zhao junwei NIU Jingyang Institute of Molecule and Crystal Engineering School of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475001China Institute of Molecule and Crystal EngineeringSchool of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475001China Institute of Molecule and Crystal EngineeringSchool of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475001China

A 3D infinitely extended structural rare earth coordination compound with a formula of K3{[Sm(H2O)7]2Na[a-SiW11O39Sm(H2O)4]2}·14H2O has been synthesized by reaction of Sm2O3,HClO4,NaOH with a-K8SiW11O39·nH2O,and characterized by IR,UV spectra,ICP,TG-DTA,cyclic voltammetry,variable-temperature magnetic susceptibility and X-ray single-crystal diffrac-tion.X-ray single-crystal diffraction indicates that the title compound crystallizes in a triclinic lat-tice,Pi space group,with a = 1.2462(3) nm,b = 1.2652(3) nm,c = 1.8420(4) nm,α = 87.45(3)°,β = 79.91(3)°,γ = 82.57(3)°,Z = 1,R1 = 0.0778,wR2 = *** analysis reveals that Sm3+(1) coordination cation has incorporated into the vacant site of [α-SiW11O39]8? entity,forming the [α-SiW11O39Sm(H2O)4]5? *** two adjacent [a-SiW11O39Sm(H2O)4]5? subunits are combined with each other through two Sm(1)-O-W bridges accompanying the formation of dim-mer structural unit [α-SiW11O39Sm(H2O)4]210? of the title *** neighboring dimmer structural units [α-SiW11O39Sm(H2O)4]210? are linked to form the 1D chainlike structure by means of two Sm3+(2) and a Na+(1) coordination *** K+(1) cations connect the 1D packing chains constructing the 2D netlike structure,and adjacent netlike layers are also grafted by K+(2) cations to build the novel 3D infinitely extended *** result of TG-DTA curves manifests that the decomposition temperature of the title polyanionic framework is 554℃.The cyclic volt-ammetry measurements show that the title polyanion has the two-step redox processes in aqueous solution with pH = *** temperature magnetic susceptibility indicates the title compound obeys the Cruie-Weiss Law in the higher temperature range from 110 to 300 K,while in the lower temperature range from 2 to 110 K the comparatively strong antiferromagnetism in-teractions can be observed.

关键词： silicotungstic acid, Keggin structure, crystal structure, polyoxometalates, rare earth metal.

Special algorithm of enhancing underwater targetradiated dynamic line spectrum

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Journal of Systems Engineering and Electronics 2005年第4期16卷 797-801页

作者： Guo Yecai zhao junwei Chen Huawei Anhui Univ. of Science and Technology Huainan 232001 P. R. China Inst. of Acoustic Engineering Northwestern Polytechnical Univ. Xi'an 710072 P. R. China

Performance of traditional adaptive line enhancer （ALE） in suppressing Gaussian noise is low and can get worse at low input signal-to-noise ratio（SNR）. For greatly overcoming these disadvantages, feature of fourth-order cumulant （FOC） different slices for quasi-stationary random process is analyzed, fourth order cumulant（FOC） different slice-based adaptive dynamic line enhancer is presented, and output SNR of the proposed enhancer is derived and bigger than that of the ALE via theoretical analysis. Simulation tests with the underwater moving target-radiated data have shown that the proposed enhancer outperforms the ALE in suppressing Gaussian noise and enhancing dynamic line spectrum feature.

关键词： higher-order cumulant different slice dynamic line spectrum underwater moving target Gaussian noise.

Analysis of CVC roll contour and determination of roll crown

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Journal of University of Science and Technology Beijing 2007年第4期14卷 378-380页

作者： Guang Xu Xianjun Liu Jiarong zhao junwei Xiong Key Laboratory of the Ministry of Education for Ferrous Metallurgy and Resources Utilization Wuhan University of Science and Technology Wuhan 430081 China

Mathematical analysis of continuous variable crown （CVC） roll contour used in CSP production line was conducted and the roll contour function of CVC roll was obtained. The validation with actual CVC roll contour shows that the calculation values of the roll contour function and the actual roll contour parameters given by equipment provider are the same, which proves that the roll contour function of CVC rolls given in this article is correct. The nonlinear relationship between the roll crown of CVC rolls and roll shift amounts was deduced. The concept of crown extremum was given.

关键词： CVC roll roll contour crown extremum axial shift

Energy Minimization for Heterogenous Traffic Coexistence with Puncturing in Mobile Edge Computing-Based Industrial Internet of Things

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China Communications 2024年第10期21卷 167-180页

作者： Wang Xue Wang Ying Fei Zixuan zhao junwei School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Laboratory of Networking and Switching Technology Beijing 100876China

Puncturing has been recognized as a promising technology to cope with the coexistence problem of enhanced mobile broadband(eMBB) and ultra-reliable low latency communications(URLLC)traffic. However, the steady performance of eMBB traffic while meeting the requirements of URLLC traffic with puncturing is a major challenge in some realistic scenarios. In this paper, we pay attention to the timely and energy-efficient processing for eMBB traffic in the industrial Internet of Things(IIoT), where mobile edge computing(MEC) is employed for data processing. Specifically, the performance of eMBB traffic and URLLC traffic in a MEC-based IIoT system is ensured by setting the threshold of tolerable delay and outage probability, respectively. Furthermore,considering the limited energy supply, an energy minimization problem of eMBB device is formulated under the above constraints, by jointly optimizing the resource blocks(RBs) punctured by URLLC traffic, data offloading and transmit power of eMBB device. With Markov's inequality, the problem is reformulated by transforming the probabilistic outage constraint into a deterministic constraint. Meanwhile, an iterative energy minimization algorithm(IEMA) is *** results demonstrate that our algorithm has a significant reduction in the energy consumption for eMBB device and achieves a better overall effect compared to several benchmarks.

关键词： energy minimization enhanced mobile broadband(eMBB)and ultra-reliable low latency communications(URLLC)coexistence industrial Internet of Things(IIoT) mobile edge computing(MEC) puncturing

Influencing factors analysis of helmet wearing for electric bicycle riders based on ordinal multinomial logistic model

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Transportation Safety and Environment 2022年第1期4卷 63-75页

作者： Quan Yuan Haixu Shi junwei zhao Ruimin Li State Key Laboratory of Automotive Safety and Energy School of Vehicle and MobilityTsinghua UniversityBeijing 100084China School of Transportation Science and Engineering Beihang UniversityBeijing 102206China Institute of Transportation Engineering Department of Civil EngineeringTsinghua UniversityBeijing 100084China

The helmet of riders of electric bicycles plays an important role in reducing injuries and deaths in traffic *** paper conducts a questionnaire survey,data analysis and modelling to investigate the influencing factors of electric bicycle helmet ***,living area,gender,age,marital status and education level are selected as independent variables for data *** factor analysis divides the sentiments of electric bicyclists for wearing helmets into four aspects:safety perception,practical sensation,satisfaction perception and emergency perception,and ordinal multiple logistic models are built to analyse the influencing *** result shows that people aged 18−25,26−35,36−45 and 46−55 are 1.3,1.8,2.0 and 2.3 times more likely,respectively,to have at least a grade higher safety perception than those aged 56 and over;men are 0.77 times more likely than women to feel at least one grade higher about the practical perception and 1.48 times more than women about the satisfaction perception;people with primary school,junior high school,senior high school,junior college and bachelor’s degree education are 1.64,2.44,1.50,1.70 and 1.55 times more likely,respectively,than people with a master’s degree to feel at least one grade higher about the satisfaction perception.

关键词： traffic safety electric bicycle helmet logistic model influencing factors

Early Permian–Late Triassic Magmatism in the Tuotuohe Region of the Qinghai–Tibet Plateau: Constraints on the Tectonic evolution of the Western Segment of the Jinshajiang Suture

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Acta Geologica Sinica(English Edition) 2014年第2期88卷 498-516页

作者： QIAN Ye SUN Fengyue LI Bile LI Shijin zhao junwei College of Earth Sciences Jilin University Qinghai Geological Survey No.5 Geological and Mineral Survey Institute of Qinghai Province

In this paper we present new zircon U-Pb ages,whole-rock major and trace element analyses,and zircon Hf isotopic data for magmatic rocks in the Tuotuohe region of the western segment of the Jinshajiang *** aim is to constrain the Early Permian-Late Triassic tectonic evolution of the *** from the magmatic rocks of the Tuotuohe region are euhedralsubhedral in shape and display fine-scale oscillatory zoning as well as high Th/U ratios （0.4-4.6）,indicating a magmatic *** zircon U-Pb ages obtained using LA-ICP-MS are 281 ± 1 Ma,258 ± 1 Ma,244 ± 1 Ma,and 216 ± 1 Ma,which indicate magmatism in the Early Permian-Late Triassic.A diorite from Bashihubei （BSHN） has SiO2 =57.18-59.97 wt％,Al2O3=15.70-16.53 wt％,and total alkalis （Na2O ＋ K2O） =4.46-6.34 wt％,typical of calc-alkaline and metaluminous series.A gabbro from Bashibadaoban （BSBDB） belongs to the alkaline series,and is poor in SiO2 （45.46-54.03 wt％） but rich in Al2O3 （16.19-17.39 wt％） and total alkalis （Na2O ＋ K2O =5.48-6.26 wt％）.The BSHN diorite and the BSBDB gabbro both display an enrichment of LREEs and LILEs and depletion of HFSEs,and they have no obvious Eu anomaly; they have relatively low MgO contents （2.54-4.93 wt％）,Mg# values of 43 to 52,and low Cr and Ni contents （8.07-33.6 ppm and 4.41-14.2 ppm,respectively）,indicating they differentiated from primitive mantle *** have low Nb/U,Ta/ U,and Ce/Pb ratios （1.3-9.6,0.2-0.8,and 0.1-18.1,respectively）,and their initial Hf isotopic ratios range from ＋9.6 to ＋16.9 （BSHN diorite） and ＋6.5 to ＋12.6 （BSBDB gabbro）,suggesting their primary magmas were derived mainly from the partial melting of a mantle wedge that had been metasomatized by subduction *** all the new data together,we conclude that the western and eastern segment of the Jinshajiang suture regions underwent identical processes of evolution in the Early Permian-Late Triassic：oceanic crust subduction before the Early Permian,continental collision during the Early-Middle T

关键词： zircon U-Pb chronology zircon Hf isotopes geochemistry tectonic setting Tuotuohe region Jinshajiang suture Qinghai-Tibet Plateau

A unique organic-inorganic hybrid Fe^(Ⅲ)–Pr^(Ⅲ)-included 2-germano-20-tungstate and its electrochemical biosensing properties

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Chinese Chemical Letters 2022年第5期33卷 2630-2634页

作者： Xiaoyi Liu Limin Cui Jun Jiang Fan Ji junwei zhao College of Chemistry and Chemical Engineering Henan UniversityKaifeng 475004China

An organic-inorganic hybrid Fe^(Ⅲ)–Pr^(Ⅲ)-included 2-germano-20-tungstate[Pr(H_(2)O)_(8)]2 H_(2)[Fe_(4)(H_(2)O)_(4)(pca)_(4) Ge_(2)W_(20)O_(72)]•34H_(2)O(Hpca=2-pyridinecarboxylic acid)(1)was hydrothermally *** polyoxoanion comprises one tetra-Fe^(Ⅲ)incorporated[Fe_(4)(H_(2)O)_(4)(pca)_(4) Ge_(2)W_(20)O_(72)]^(8-)hybrid entity and two[Pr(H_(2)O)_(8)]^(3+)ornamental ***[Fe_(4)(H_(2)O)_(4)(pca)4 Ge_(2)W_(20)O_(72)]^(8-)2-germano-20-tungstate entity can be regarded as an infrequent S-type[Ge_(2)W_(20)O_(72)]^(16-)cluster pocketed by four[Fe(H_(2)O)(pca)]2+*** S-type[Ge_(2)W_(20)O_(72)]16-cluster could be imagined as condensation of two divacant Keggin[α-GeW _(10)O_(37)]^(10-)segments by sharing two *** is of interest is that carboxyl O and pyridine N atoms on pca ligands concurrently bind with Fe ^(3+)cations in a five-membered heterocyclic fashion to increase the stability of the whole ***,the electrochemical biosensing properties of 1 as the modified electrode material have been investigated for detecting norepinephrine(NPP),showing a low detection limit of 3.25μmol/*** work not only enriches structures of heterometallic german-otungstates(GTs),but also expands applications of polyoxometalates(POMs)in the electrochemical biosensing field.

关键词： Polyoxometalate Germanotungstate Heterometallic polyoxotungstate Electrochemistry Biosensing

Hydroxyl-and-carboxyl ligand concatenating multi-lanthanide substituted tellurotungstates and electrochemical detection of noradrenaline

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Journal of Rare Earths 2022年第11期40卷 1785-1793,I0005页

作者： Mengling Liu Yan Zhang Jun Jiang Dan Wang Yanzhou Li junwei zhao Lijuan Chen Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China

Developing and exploring organic-inorganic hybrid multi-lanthanide(Ln)implanted heteropolyoxometalates(HPOMs)has bloomed into an emerging research *** this article,two neoteric Dgluconic acids(H_(6)GA)concatenating multi-Ln^(Ⅲ) implanted heteropoly tungstates K_(14)H_(10)[Ln_(4)(H_(2)O)_(4)W_(6)(H_(2)-GA)_(4) O_(12)(B-α-TeW_(9)O_(33))_(4)]·60 H_(2)O(Ln=La^(3+)(1),Pr^(3+)(2))were obtained in acidic aqueous ***,in the polyanion structure of 1 and 2,six WⅥand four LnⅢcenters are connected by four flexible H_(2)GA^(4-) ligands via carboxyl and hydroxyl groups,resulting in the heterometallic[Ln_(4)(H_(2)O)_(4)W_(6)H_(2)GA)_(4)O_(12)]^(8+)cluster and then the heterometallic cluster is surrounded by four[B-α-TeW_(9)O_(33)]^(8-)*** measurements for the 1@CFMCN/GCE sensor(CFMCN=carboxylfunctionalized multiwalled carbon nanotube;GCE=glass carbon electrode)demonstrate that 1@CFMCN/GCE shows benign recognition response to detecting noradrenaline(NDA).This research expands the structural diversity of Ln-implanted HPOMs and presents an electrochemical platform of recognizing NDA in the field of biosensors.

关键词： Polyoxometalate Tellurotungstate Lanthanide Gluconic acid Electrochemical sensing Rare earths

Rice MtN3/saliva/SWEET gene family: Evolution,expression profiling, and sugar transport

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Journal of Integrative Plant Biology 2014年第6期56卷 559-570页

作者： Meng Yuan junwei zhao Renyan Huang Xianghua Li Jinghua Xiao Shiping Wang National Key Laboratory of Crop Genetic Improvement National Center of Plant Gene Research (Wuhan) Huazhong Agricultural University

The rice MtN3/saliva/SWEET gene family consists of 21 paralogs. However, their functions in physiological processes are largely unknown, although at least three of the 21 paralogs are used by pathogenic bacteria to infect rice. Here, we report the evolutionary features, transcriptional characteristics, and putative functions in sugar transport of this gene family. The wild rice accessions in this study included those with AA, BB, CC, BBCC, CCDD, EE, and GG genomes, which appeared approximately 0.58-14.6 million years ago. The structures, chromosomal locations, phylogenetic relationships, and homologous distribution among the accessions suggest that the number of rice MtN3/saliva/SWEET paralogs gradual y increased as the Oryza genus evolved, and one third of the paralogs may have originated recently. These paralogs are differentially expressed in vegetative and reproductive tissues, in the leaf senescence process, and in signaling dependent on gibberel ic acid, cytokinin, or 1-naphthalene acetic acid （an analog of auxin）, suggesting that they may be associated with multiple physiological processes. Four paralogs could transport galactose in yeast, which suggests that they may have a similar function in rice. These results will help to elucidate their roles and biochemical functions in rice development, adaptation to environment, host-pathogen interaction, and so forth.

关键词： Evolution MtN3/saliva domain Oryza sotivo transporter